What grows there?

'Misty Blue' White Baneberry is Doll's Eye

2011-03-06T08:48:00.000-08:00

Discovered at MT. Cuba Center in Delaware is a striking mult-stemmed woodland perennial with soft bluish-green finely cut foliage. Plants flower white in April snd white doll's eye fruit form in the fall. The snow white berries are clustered on bright red pedicels. Each is marked with a distinctive black dot. Fruit persists for 4-6 weeks. This long-lived perennial thrives in moist, well-drained, rich woodland soil. Plants grow 2-3 feet tall and are best grouped en masse. Actaea is reliably hardy through USDA zones 3-8

Pruning Hydrangeas

2011-03-03T13:28:00.000-08:00

Photo: Hydrangea paniculata 'Limelight'

PeeGee or panicled hydrangea (Hydrangea paniculata) or the native Smooth hydrangea (Hydrangea arborescens) are pruned in early spring because they bloom on the current season’s wood. If you feel the need, these plants could be cut to about 4 inches from the ground in early spring and will produce new shoots and blooms during the season.

New Website at whatgrowsthere.com!

2010-10-10T12:55:00.000-07:00

I've been working on my new website, What Grows There and have moved this blog over to that location. All new posts will be there. Enjoy! http://www.whatgrowsthere.com

New Intersectional Peonies Deserve A Wow!

2010-10-09T09:00:00.000-07:00

Photo: tree peony at Staten Island Botanical Gardens
Itoh or Intersectional Hybrid Peonies (Paeonia spp.) represent a huge breakthrough in tissue culture propagation. Inherited from the tree peony is attractive dissected foliage. They are extremely winter hardy like the herbaceous types.

Plants grow two to three feet tall and wide. Strong sturdy stems support the huge flowers which size up to 10" across. Flowers are single, semi-double or double, and available in a wide range of colors including yellow. Flowers stand upright even in heavy rain and require no staking. Bloom time is longer due to additional flowers being produced on side shoots.

Peonies are long-lived, growing in the same location for decades. They need to be properly nourished annually. Peonies prefer full to part sun (minimum of 6 hours per day), average moisture and well-drained soil which is enriched with compost or mulch annually.

Bare-root peonies should only be planted in the fall as this coincides with the time that their tubers develop most of their feeder roots. Container-grown peonies can be planted at any time. Itoh hybrids demonstrate good resistance to peony blight (Botrytis paeoniae).

Proper planting depth is very important for peonies. The crown should be planted 1½ - 2 inches below soil level. If the eyes have already begun to grow, the new growth may be set slightly above the surface.

Itoh peonies are now available through e-commerce nurseries.

Tips on Planting Peonies

2010-10-06T09:59:00.000-07:00

Peonies (herbaceous types) are old-fashioned perennial favorites garnering new attention from 21st century gardeners. Their gorgeous spring flowers stand tall above the lush shrubbery growth.

This fall, plant dormant bare-root divisions of herbaceous peonies purchased from a mail-order nursery or a nearby garden center. Each division must exhibit 3 to 5 eyes (buds). Space plants a minimum of three feet apart.

Good air circulation around plants is important to prevent potential foliar and flower diseases. Avoid windy areas and shelter plants from harsh summer sun and heat in warmer climates (USDA zones 7-9).

Peonies thrive in gardens for 20 or more years. Select a sunny spot with well-drained garden soil and enrich with generous amounts of compost or well-rotted manure. A soil pH between 6 and 7 is ideal. Feed peonies with a slow release fertilizer in early spring the same as you would nourish flowering shrubs.

A critical digging step is the planting depth. Do not cover the growing eyes with more than 1 inch of soil. Setting the new plant too deep may delay or even prevent flowering. Water the newly planted peonies and cover the bed with 2-3 inches of loose ground up leaves or bark mulch. Likely, the peonies will bloom next spring and many years thereafter.

Tree peony culture will be discussed in a future blog.

Goldenrod --Set Off Some Fireworks This Fall

2010-10-03T09:38:00.000-07:00

Rough-stemmed goldenrod (Solidago rugosa) grows in low woods, meadows and bogs in the eastern half of North America.. ‘Fireworks’ (USDA zones 4–8) has a more compact plant habit than the species. This early blooming cultivar provides a long floral show starting in mid-August and lasting thru Thanksgiving, weather permitting.

Flowers spikes are numerous and held in tight clusters on upright stems. The yellow, thread-like, cascading sprays of flowers do attracts many insect pollinators; the pollen does not cause allergies as once believed.

Goldenrods grow best in full sun to light shade. While they prefer moist, well-drained, slightly acidic soil, established plants flourish in hot, humid and dry summers. Surprisingly, goldenrod tends to grow weak lateral shoots in soils that are organically rich.

'Fireworks' spreads quickly by seed and underground rhizomes and needs to be divide every 2-3 years . This upright herbaceous perennial grows 3 - 4 feet tall and 2 – 2.5 feet wide. Remove old flowers to encourage re-blooming. Deadhead or remove spent blooms on 'Fireworks' to generate added lateral floral sprays into late October and November. Removal of seed heads reduces re-seeding threat.

Fall Planting Deadline for Pansies and Violas

2010-09-30T09:31:00.000-07:00

To grow pansies successfully, follow this four- step program. Start with: 1. Purchasing healthy plants, 2. Planting by mid-October or earlier, 3. Watering in the fall and winter as needed, and 4. Fertilizing monthly through the winter and spring months.

Shop for vigorous dark green plants at local greenhouses and garden centers. Closely inspect for lots of white growing roots. Don’t buy short or spindly seedlings or those with yellowing leaves. Purchase sturdy 1801 plants (18 - 3 ½” plant cells per tray) or larger pots. Small pansies tend to be more disease susceptible. To avoid deadly root rot diseases in garden soils, move pansy/viola beds every three years.

Over much of the Southern Appalachian region (USDA zones 6-7), the completion date for planting pansies and violas is October 15th. Back up a week or two earlier if planting in gardens at higher elevations. An earlier fall planting date allows plants adequate time to root down into the warm autumn soil. Deeply rooted plants bloom heavier through the fall and winter seasons.

Large sized plants start off quickly and fall-winter flowering is better. Deeply rooted pansies and violas provide better anchorage, which prevents a chance of winter freeze heaving. Once soil temperatures drop below 45°F, plant growth slows and flower numbers decline.

There are many series of pansies and violas to choose in colors ranging from white, yellow, pink, red, and purple shades. Color patterns may be clear, blotched or picotee. Four popular pansy series are Delta®, Matrix®, Panola®, and Majestic Giant ll™. Among the popular viola series are Sorbet®, Rocky™, Penny™ and Velour™.

Prepare the garden bed or containers prior to planting. Pansies should be planted in well-drained, organically rich garden soil or container media mix. An acidic soil pH ranging between 5.2 - 5.8 avoids natural deficiencies in iron and manganese. Adding lime to pansy beds is usually unnecessary unless recommended after a soil test. Pansies thrive in full sun to partial shade. Plants grow more compact and bloom heaviest in full sun.

Franklinia - Native Tree Lost in the Wild

2010-09-27T13:40:00.000-07:00

Franklinia (Franklinia alatamaha) is a wonderful small tree or large multi-trunked shrub with fragrant white camellia- like flowers. Franklinia is related to world-class flowering shrubs like camellia and stewartia. Its white 3 - 3 ½ inch camellia-like flowers appear from early August thru late September.

Franklinia is winter hardy in the Southern Appalachian region (USDA zones 6-7). Its fibrous root system prefers a well-drained, richly organic, and acidic soil much like azaleas and rhododendrons. Don’t subject to extended summer droughts or frigid drying winter winds.

Fall color is respectable with autumnal hues of red, orange and burgundy. The bark on a young tree is distinctively striped, and the main branches become fissured with age.

The species was discovered by plant explorer John Bartram and his son William growing along the Alatamaha River in southeastern Georgia in 1765. Natural populations are now extinct. All franklinia trees growing today are descendants of the Bartrams’ collected seeds.

Franklinia is a finicky grower, but very much worth the challenge. A deadly fungal root disease, Phytophthora cinnamoni, may have led to its demise in nature, is its Achilles’ heel. A 2-3 week long invasion of Japanese beetles in August may shorten individual bloom life by half.

Substitute Dwarf Cryptomeria for Yews and Japanese Holly

2010-09-25T12:44:00.000-07:00

For better garden performance and different textural look around a home foundation, plant the dwarf shrub forms of Japanese cedar (Cryptomeria japonica). Dwarf cryptomeria is an excellent substitute for Japanese yews (Taxus spp.) or 'Helleri' hollies (Ilex crenata) which often struggle in heavy clay soils, particularly those poorly drained.

'Globosa Nana' (photo) has a "cookie-cutter" round, globular form, and rarely needs pruning. 'Globosa Nana' has bright green floiage and grows 3-6 feet tall and wide. The cultivar 'Black Dragon' has dark green foliage and a pyramidal growth habit (8-12 feet tall and 4-5 feet wide). Both are planted as single specimens or grouped several together They are slower growing than their taller 40-50 feet columnar counterparts.

Cryptomerias prefer well-drained, slightly acidic soil and are planted in an open sunny location. Young shrubs are remarkably shade tolerant. Their dark evergreen foliage turns a bronze to purple color during the coldest part of winter. By early spring the bright or dark green color returns to their short needles. Fertilize shrubs annually either in February or March.

Garden centers sell either balled and burlapped (b&b) or container-grown stock. Cryptomeria is best planted from February thru October. This evergreen demonstrates superior heat and drought tolerances once established in the landscape for two years.

Truly, Fall Is For Planting

2010-09-22T08:46:00.000-07:00

Photo: Fall displays have arrived at area garden centers with this lovely bin of gourds

The seasonal theme at garden centers today is "Fall is for Planting". Plant sales are everywhere. If you have recently purchased a home and your budget is tight, buy yourself an early, but practicable holiday gift- a deciduous shade tree planted along the southwest side of the home. In a few short years, this tree will reward you with valuable shade and lower summer cooling bills.

Some good deciduous choices are red maple, green ash, tulip poplar, sweetgum, willow oak, and basswood. Garden centers push to reduce store inventories, saving you 30%-50% off the list price. I offer these six basic landscape planting tips:

1. Plant only deciduous trees in the front of your home, and evergreen trees (pines, hollies, hemlock, etc.) elsewhere
2. Dig a hole three times wider and shallow enough to accomodate the diameter of the root ball
3. Plant shallow, barely covering the root ball and add no soil amendments
4. Apply three inches of an organic mulch (wood chips, pine straw or compost) over the surface
width of the planting hole and do not pile mulch up against the trunk
5. Slowly pour a minimum of 10 gallons of water to each tree after planting
6. Do not fertilize fall-planted trees and shrubs until late February or March.

Ivy Geranium 'Lila Compact'

2010-09-19T11:50:00.000-07:00

Ivy-leaf geraniums (Pelargonium peltatum) owe their name to their leaf shape. While zonal geraniums are favorites in garden beds, the vining or cascading ivy geraniums excel in hanging baskets, containers and window boxes.

Earlier this month I spotted this lavender beauty called ‘Lila Compact’ Cascade™ (photo) in downtown Asheville, NC. City grounds crews have hand-watered all plants over a 5-6 block area every morning since mid-May.

Improved modern cultivars exhibit better heat and drought tolerances than in the past. Newer cascading varieties of ivy geraniums are also more floriferous. Ivy-leaf geraniums grow best in cool climates and lots of sun. They handle 85°F summer temperatures for short stretches. In warmer areas of zone 7, place containers in partially shaded exposures. Ivy leaf geraniums don’t hold up to long periods of drought. They are planted outdoors after threats of spring frosts have passed and the soil/media has warmed up.

The single flowering types produce more blooms than the semi-double flowering varieties. Plants hold their compact form throughout the summer months. Many colorful varieties are available -- from 12” sized miniatures to the vigorous 4- 5 feet cascading types highlighted here.

Coppicing - Renewal Pruning for Old Rhododendrons

2010-09-15T11:00:00.000-07:00

Photo: when rosebay rhododendron (R. maximum) gets too tall and leggy, coppice (prune back) in late September and October

Coppicing is a no-brainer form of renewal pruning. The entire shrub is lopped off to the ground to re-start from its roots next spring. For many gardeners, it's a gutsy move, but a fairly simple task. Coppicing also eliminates disease and/or insect- riddled stems and twigs without resorting to pesticides.

Timing is critical. Overgrown rhododendrons, including deciduous azaleas, hollies, pieris and mountain laurels may be coppiced from late September thru October. Coppicing invigorates old shrubs, brightens foliage color and increases fruit size.

Very important: over-grown shrubs should be well-established and healthy; old rhodies in poor health will likely not re-grow. Rhodies may be cut back severely to stumps with no leaves. Healthy plants recover quickly vegetatively, but do not flower for two, sometimes three years.

A coppiced plant sometimes re-grow so vigorously that some additional pruning will be necessary. Many new shoots (stems) will emerge; select the most straightest and most vigorous.

Hand clippers, loppers, and saws should be sharp. Do not use weed-eaters.

Rooting Proliferations on Daylilies

2010-09-11T06:05:00.000-07:00

Photo: daylily proliferations on old floral scape in late August

Proliferations are small plants which grow on the spent floral scapes of daylilies (Hemerocallus spp.). Not all daylily varieties produce proliferations. Propagating and growing proliferations is a simple way to increase the number of new daylily plants quickly.

Prune off each plantlet from the old floral scape as they form. Stick each one into a prepared ground bed. Label or tag the cultivar from which the proliferation is taken. Over the next two weeks, keep the soil/media moist. The proliferations will expand their roots into the media.

An alternative approach is to set each proliferation into its own 4-6 inch pot containing coarse sand or soil-less media or mix. Keep the media moist and grow new daylily plant into late fall. If you live in a cold winter (USDA zone 6 and colder), bury the pot to prevent serious freeze injury or grow in a protected cold frame. In areas experiencing mild winters (USDA zones 7 and warmer), transplant newly rooted plants into a ground bed before November 1st.

Plantlets should begin flowering within 18-24 months. If, in haste, you had removed the old floral scapes after spring bloom, don't be in quite a hurry next summer.

Fall Blooming Perennials

2010-09-08T06:01:00.000-07:00

Photo: Fall anemone 'Honorine Jobert'

The end of summer does not mean that other perennials aren't beginning their blooming season. Three fall flowering perennials- reblooming daylilies, remontant iris, and fall anemones- thrive here in the Southern Appalachian (USDA zones 6 and 7).

Early fall is a great time to again enjoy a lovely bed of re-blooming daylilies (Hemerocallus spp.). 'Stella D'Oro' (golden yellow), the most popular variety for the past quarter of the century, was recently dethroned by 'Happy Returns' (light yellow). 'Pardon Me' (red) is another re-blooming favorite. Inter-planting daffodils, tulips or hyacinths among the daylily clumps extends your floral calendar another month or two.

Remontant iris (Iris spp.) re-bloom a second time from August through November. The trick to re-blooming daylilies and irises is to provide some relief from summer drought stress. Weekly deep watering is certain guarantee of repeat fall bloom.

Fall anemones (Anemone x hybrida) are available in many colorful varieties, starting with an old favorite and garden performer 'Honorine Jobert' (2-3 " single white blooms), 'Queen Charlotte' (3" semi-double pink), 'September Charm' (3" single rose-pink), and 'Whirlwind' (4" semi-double white).

Do not grow fall anemones in direct full day sun. Plants prefer a partial sun to partial shady spot. Caution: plant in spring thru mid-summer to permit adequate time to establish their roots. Anemones perennialize easily when planted in richly composted, well-drained garden soil.

'Sunshine Daydream' Helianthus for Mid-Summer Bloom

2010-09-03T17:00:00.000-07:00

Sunshine Daydream (Helianthus x multiflorus ‘Sunshine Daydream’) has been blooming non-stop in my Northeast Tennessee garden for the past two months.

This double-flowering yellow false sunflower is a new introduction from North Creek Nurseries, a wholesale nursery in Landenberg, PA. Sunshine Daydream is a branch sport (mutation) of native cultivar ‘Capenoch Star’. It is a mid-summer flowering perennial.

Sturdy 5 - 6 feet tall by 2 - 4 feet wide plants support bouquets of bright yellow double flowers. The dahlia-like blooms measure 2.5 inches across. The spent flowers are seedless and do not threaten to become a weedy problem in years to come.

Sunshine Daydream performs best in full sun, preferably in moist well-drained soil. Keep plants in full vigor with monthly applications of a water-soluble fertilizer such as Miracle -Gro™ or equivalent or feed bi-monthly with 10-10-10 or equivalent.

Sunshine Daydream stands up to summer's heat and humidity. Established 1- year old plants are moderately drought tolerant. This long-lived perennial is hardy in USDA zones 4 thru 8. The summer foliage of Sunshine Daydream is remarkably resistant to powdery mildew, a fungal disease which plagues some helianthus species.

Potential Epidemic In Your Car Trunk Or Camper?

2010-08-31T17:30:00.000-07:00

Photo: walnut twig beetle infestation

Tennessee Department of Agriculture (TDA) officials urge state residents and visitors to the state to help prevent the spread of Thousand Cankers Disease in black walnut (Juglans nigra)trees and Emerald Ash Borer in ash species (Fraxinus spp.). Take the following steps:

 Don’t transport firewood, even within Tennessee. Don’t bring firewood along for camping trips. Buy the wood you need from a local source. Don’t bring wood home with you.

 Don’t buy or move firewood from outside the state. If someone comes to your door selling firewood, ask them about the source, and don’t buy wood from outside the state.

 Watch for signs of walnut twig beetle infestation in your black walnut trees. If you suspect your black walnut tree is infested with TCD, visit www.TN.gov/agriculture/tcd for an online symptoms checklist and report form or call TDA’s Regulatory Services Division at 1-800-628-2631.

Mulching- Not Always a Good Practice

2010-08-29T08:19:00.000-07:00

A generation of gardeners have extolled the benefits of mulching around trees and flower beds. Sometimes, mulching is not a good practice.

Often, a heavy clay soil retains too much moisture over the winter months. Some dryland perennials, such as cheddar pinks (dianthus), euphorbia, and delospermum, prefer dry to moderately wet winter soils. Amending with coarse sand improves soil drainage, but adding mulch may be counter-productive.

Quality mulch contains very little cellulose (wood) fiber. A wood based mulch attracts structural wood -feeding insects such as termites, carpenter ants, and wood beetles. Wood-based mulches should not be spread around home foundations.

Fresh wood-based mulch grabs up available soil nitrogen. Nitrogen -starved plants appear yellowed (chlorotic). You may need to apply 2-4 times the amount of fertilizer to counteract the wood mulch.

Piling up mulch around the base of trees, called "mulch volcanoes", will damage tree trunks. Surface roots are deprived of oxygen. Often, weak adventitious roots grow in the mulch. When the mulch dries out, the weak roots die and scar the trunk.

Young fruit trees should not be mulched in the fall and winter where field mice (voles) are suspected. The voles create a home in the mulch and feed on live roots and soft tree bark.

Zones 6 Winter Hardy Encore Azaleas™

2010-08-25T16:05:00.000-07:00

'Autumn Ruby' Encore azalea in April 2009

Photo credit: Dr. Alan Windham, Extension Plant Pathologist, University of Tennessee

Encore Azaleas™ bloom twice: in the spring and from late summer into the fall season.
Ten varieties consistently exhibited cold hardiness throughout zones 6-a and 6-b: Autumn Amethyst, Autumn Carnation, Autumn Cheer, Autumn Lilac, Autumn Royalty, Autumn Ruby, Autumn Sangria, Autumn Sundance, Autumn Sunset, and Autumn Twist.

In Zone 6-b, nine additional varieties also consistently exhibited exceptional cold hardiness: Autumn Bravo, Autumn Carnival, Autumn Debutante, Autumn Embers , Autumn Empress , Autumn Monarch, Autumn Princess, Autumn Rouge, and Autumn Sweetheart.

For best results in plant zones 6-b and colder, gardeners should plant in the spring or early summer. In Zones 7-9, Encore Azaleas benefit from fall and late summer planting schedules. Their multi-season blooms make them ideal for container gardens.

Encore azaleas™ begin blooming each spring like traditional azaleas. These evergreen azaleas enjoy more sun than traditional azaleas. Encore Azaleas were bred by Robert E. “Buddy” Lee of Independence, Louisiana and are available at many independent garden centers.

Chinese (Kousa) Dogwood Doesn't Like Extreme Heat

2010-08-22T13:56:00.000-07:00

photo: leaf curl on kousa dogwood
Never forget the adage: "the right plant in the right location". In USDA hardiness zone 7 and warmer parts of zone 6-b, Chinese dogwood (Cornus kousa) does not cope with excessive summer heat well. A typical stress response is leaf curling. On more stressful droughty sites, leaf margins and centers will likely burn.

The young tree pictured above is planted along a suburban street, with a concrete sidewalk and street curb on two sides. Thick turf sod covers the ground beneath the tree, competing with the tree for available soil moisture and nutrients. On a hot 90°F day, this tree is likely to experience heat indices above 120°F.

Likely, the tree will survive, but not bloom dependably every spring. Leaf burning and curling reduce the tree’s ability to photosynthesize, resulting in less (or more) flower bud set. The tree will either flower poorly or bloom heavily in future springs, resulting in an alternate flowering cycle or "biennial bearing".

Kousa dogwood will handle full sun locations, provided heat and drought stresses are managed through timely irrigation. Currently, the University of Tennessee is evaluating several seedling kousa selections for better heat and drought tolerances here in the mid-South.

'Dee Runk' is Best Upright Boxwood

2010-08-21T11:11:00.000-07:00

Looking for the best upright boxwood for your garden or landscape? According to wholesale boxwood growers, Saunders Brothers Nursery in Roanoke, VA and Weigel Farms near Greensboro, NC, the best is 'Dee Runk' (pictured).

Over the past quarter century, the boxwood cultivar 'Graham Blandy' had been the standard bearer, but commercial landscapers have increasingly complained about losing plants to pythium and phytophthora root rot diseases. 'Dee Runk' and another called 'Fastigiata' possess better disease resistance. ‘Dee Runk’ is also more reliable than the root rot prone ‘Sky Pencil’ holly (Ilex crenata 'Sky Pencil').

Buxus sempervirens ‘Dee Runk’ is remarkably winter hardy (USDA hardiness zones 5-8). Growth rate is medium, reaching 10 feet in height and 3 feet in width after 15 years. New foliage begins with a bluish-green tint and matures dark green. Boxwoods are deer-resistant and pollution tolerant.

In general, boxwoods tolerate most garden light conditions from full sun or moderate shade at the edge of a woodland garden. ‘Dee Runk’ also handles poor clay sites, provided soils are well-drained.

Landscape uses: specimen, screens/formal hedges, in containers, and a foundation shrub that won’t interfere with roof eaves in future years.

Intensia® Phlox Stand Up to Summer Heat

2010-08-18T18:29:00.000-07:00

Photo: 'Intensia Lilac Rose'
The Intensia® Phlox series are the result of a cross between P. drummondii and a southwestern U.S. phlox species. Growth is low and cascading which makes this annual phlox ideal for planting in the front garden border. Equally, Intensia® Phlox excel in mixed containers, window boxes, and hanging baskets.

Intensia® phlox grow to a uniform 8-12” mature height in full to partial sun (best in 6 hours or more sunlight). Intensia phlox possess exceptional heat and humidity tolerances and flower freely all summer long. Insect and disease problems are minimal, exhibiting above average powdery mildew resistance.

Annual phlox thrive in well-drained garden soil which has been generously amended with organic matter. After planting, water on a 7-10 day schedule, particularly when rainfall is not plentiful.

By mid-summer plants may appear seedy and overgrown. Mow them back to 5 inches high, add fertilizer, and irrigate. The phlox bed will perk up and re-bloom within a few weeks, and right into the autumn season.

Blooms are slightly fragrance and attract frequent visits from nectar-hungry bees and butterflies.Flower colors of the Intensia® series range from white, several pink shades, lavender, and purple.

Pruning Big Leaf Hydrangeas

2010-08-15T09:35:00.000-07:00

photo credit: Dr. Ken Tilt, Auburn University

When mophead and lacecap hydrangeas (Hydrangea macrophylla) get too tall, leggy, or have outgrown their garden space, prune them now from mid-July thru mid-August. Our native oakleaf hydrangeas (H. quercifolia) are pruned at this time as well. Remove withered or faded flowers; some new flowers may replace those that you have deadheaded in September.

These two hydrangea species set their flower buds for next spring on old or current season’s growth on the terminal bud. Pruning in the fall or winter may remove flower buds or stimulate soft late shoots which die over the winter. Make all cuts at 1/4 inch above the last set of leaves (see photo) or cutback flush to a main branch.

Pruning improves the health of the plant, increasing vegetative growth. On older 4-5 year old hydrangeas, remove larger, thicker canes and prune them at the base of the stem. Remove one-quarter to one-third of these older branches. In 3-4 years the hydrangea will be completely rejuvenated.

Dead, dying, diseased stems and flowers can be removed at any time of year.

A Perfect Year for Hortensia Hydrangeas

2010-08-13T13:05:00.000-07:00

2010 has been an exceptional year for big leaf hydrangeas (Hydrangea macrophylla), also called “hortensia” hydrangeas. Consecutive year blooming rarely occurs here in the southern Appalachian region (USDA zones 6 and 7). ‘Nikko Blue” hydrangea, which has not bloomed for over 15 years, has been beautiful in my garden this summer.

Why have big leaf hydrangeas been so “on” this summer? I asked Dr. Sandra Reed, USDA hydrangea breeder at the TN State University Nursery Crops Research Station in McMinnville. Sandra’s response… “the weather”. The 2009 autumn was unusual. October and November temperatures gradually declined. The winter was cold and temps stayed cold, not fluctuating wildly. Across most areas a perfect spring followed with no severe freezes or frosts.

Finally, new hardier cultivars are available such as Endless Summer®, ‘Penny Mac’, and ‘Pia’ (lacecap type). These varieties are remontant, able to bloom on either old or new wood.

If your hydrangea(s) did not bloom this year, check the plant’s light exposure and nutrition. Hortensia types want a minimum of one-half day sunlight, preferably in the morning. Feed shrubs in early spring with a water soluble or slow-release fertilizer according the manufacturer’s package directions.

Cardinal Flower – A Hummingbird Magnet

2010-08-11T15:00:00.000-07:00

Cardinal flower (Lobelia cardinalis) is a hardy perennial native in USDA zones 5-8. Clumps should be divided every 2-3 years to retain plant vigor. Soil moisture determines its height and vigor.

Cardinal flower prefers half-day direct morning sunlight, particularly in more southern climes. The brilliant red flowers bloom from late July through most of September, making it a standout on their own or mixed with other perennials. Deadheading (pruning off the old floral stems) extends out its flowering period.

Cardinal flower grows 3 feet high and 2 ½ feet wide, and is taller when planted at the edge of a pond or water garden. This lobelia is at home in a rain garden, particularly when summer moisture is plentiful. Fertilize with a water soluble product monthly or feed bi-monthly with agricultural grade fertilizer (10-10-10 or equivalent) from late winter to the end of the flowering period.

Select these two cultivars -- ‘Fried Green Tomatoes’ exhibits bright green foliage which turns a deep olive color on the leaf upper surface and maroon on the underside; flowers are bright red. ‘Monet Moment’ bears exquisite rose-pink flowers. Blooms on both cultivars are exceptionally larger than species.

Summertime Is Here...So Is Locust Leaf Miner

2010-08-08T11:32:00.000-07:00

Photo: 'Freesia' black locust tree
Some trees take on a dead brownish look along highways in the summer months across the southern Appalachian region (USDA zones 6 and 7). Over the past month, locust leaf miner have been feeding on black locust (Robinia pseudoacacia) trees, stripping chlorophyll from the leaves.

Something to worry about? Generally, no. Spraying insecticides is usually not necessary. By late June black locust trees have completed their "photosynthetic life cycle" and foliar injury does not prevent old established trees from starting fresh next spring.

Generally, American gardeners have always had a low opinion about our native black locust. However, new black locust cultivars are awakening our interests. To list three exciting cultivar introductions- try Twisty Baby™ with lacy foliage and twisted shoots, 'Purple Robe’ with dark red-rose flowers, and golden leaved 'Frisia'. These young trees need insect protection.

A time-saving, environmentally safe treatment is a soil application of imidaclopyrid (Bayer Advanced Garden Insecticide™) in early spring. Simply, the pesticide is applied to the ground under the tree and watered in (according to label directions). This prevents beetle larvae development in the spring, and eliminates the threat of the summer leaf skeletonizing adults.

An alternative summer treatment is to spray any pyrethoid insecticide labeled for landscape trees and shrubs. Spraying large trees are a chore, requiring two or more applications over a 4-6 week period.

'Notify Grounds Crew' Daylily

2010-08-05T07:42:00.000-07:00

What's in a name? During our July pilgrimage to Kingwood Center in Mansfield, Ohio, I photographed this unlabelled daylily. It towered over all other daylilies in the large display bed. Of course, my curiosity go the better of me, and I had to know its name.

Mystery solved, thanks to Mr. Charles Applegate, Kingwood gardener for the past 42 years. Charles called me, and provided the pedigree of 'Notify Ground Crew'. What a great name, one that I will not likely to forget.

'Notify Ground Crew" is a mid-season tetraploid bloomer. It exhibits extremely tall 72-inch high floral scapes and is well-branched (see photo). Cheery, 5 inch wide, bright yellow flowers tower above all other daylily varieties in the bed. It was bred by Curt Hanson in Michigan and introduced in 2000. It is very modestly priced and available from several on-line nurseries.

Arkansas Amsonia - 2011 Perennial Plant of the Year

2010-08-02T16:01:00.000-07:00

Since 1990, the Perennial Plant Association (PPA) has annually selected one outstanding perennial for gardeners to enjoy. Last week, at the annual PPA Symposium in Portland, OR, members selected Arkansas amsonia (Amsonia hubrichtii) as the 2011 Perennial Plant of the Year.
Why wait until next year to purchase amsonia? It is available now through many garden centers, mail order, and on-line nurseries. Amsonia begins its rapid growth in early April. A month later, the 3 foot tall and wide plants are blooming. Pale “bluestar” flowers bloom over 2-3 weeks in the southern Appalachian region (USDA zones 6 and 7).
Flowering is just a prelude to its other attributes. Blue-green, fine textured summer foliage is devoid of serious disease and insect problems and is deer proof. In October, its foliage turns a spectacular lemony yellow. To achieve maximum autumn foliar impact, plant three or more amsonia spaced 3 to 4 feet apart.
Amsonia forms strong stems under full day sunlight; branches are weak or floppy in partial shade. It grows in any well-drained soil with a pH range from 5.6 -6.8. Established plants are heat, humidity, and drought tolerant.
Furthermore, don’t overlook another perennial favorite, bluestar amsonia (A. tabernaemontana), which will be featured in a future blog.

Plumleaf Azalea -This Gardener's Choice

2010-08-01T19:09:00.000-07:00

Plumleaf azalea (Rhododendron prunifolium) has been blooming in my garden for the past ten days. This species is a late July - early August bloomer in northeast TN. The bright orange-red flowers of this native azalea light up any garden spot whether in full sun or partial shade. Provide some additional shade in southern climes (zones 7-b and 8). A dark red flower selection is available.

It grows in any well-drained soil type- sand, silt or clay. My two established shrubs receive little nutritional care. Shrubs are irrigated during severe drought periods, such as we are in currently.
Plumleaf azalea is an Alabama/southwest Georgia native, but is winter hardy in the southern Appalachian region (USDA zones 6-7), and further north (zone 5). It seems almost soil pH insensitive, although likely prefers an acidic range between 5.4 to 6.4. No diseases and insects pests trouble it. Flowers are not fragrant, but do attract numerous butterfly and bee pollinators.

Pruning is rarely done on my 15+ year old plant purchased at Callaway Gardens. Plumleaf azalea grows 8-10 feet tall, but I maintain it at 6 by 6 feet tall and wide. An errant branch is occasionally clipped back into the fold.

Thousand Cankers Disease Found in Knoxville, TN

2010-07-29T17:20:00.000-07:00

Photo: walnut canker from Dr. Alan Windham, Extension Plant Pathologist, University of Tennessee

A black walnut (Juglans nigra) sample collected by Dr. Scott Schlarbaum, research forester at the University of Tennessee, has been confirmed as thousand cankers disease (TCD) (Geosmithia sp. nov.). Also found in the Knoxville TN walnut sample was one adult male beetle, verified as walnut twig beetle (Pityophthorus juglandis).

This is the first report of the walnut twig beetle and TCD in the native range of black walnut. TCD has killed thousands of walnut trees in the western United States and could potentially be devastating in the eastern United States as well. The extent of the outbreak in the Knoxville area is unknown at this time. The affected trees are in an urban area. Judging the sample, the disease has been present in the region for a number of years and is causing mortality.

Based on our experience TCD will be difficult, if not impossible, to stop. The hope is that the beetle and disease will behave differently in the eastern U.S. It takes 3-5 years to kill a large walnut tree. There are probably other outbreaks in the East that have not yet been noticed.

Dr. Alan Windham, UT Extension Plant Pathologist, urges foresters and others to be on the lookout for unusual dieback or mortality of walnuts, especially in urban areas. This is where TCD is likely to occur first because of movement of the beetle in wood (firewood, fresh lumber).

At this time the USDA has no federal quarantine on TCD, and this disease is not on any action lists. For further information, search: http://www.ppdl.purdue.edu/PPDL/pubs/walnutthousandcankersdisease.pdf

Pennisetum 'Karley Rose'

2010-07-25T20:05:00.000-07:00

Asian fountain grass cultivar 'Karley Rose'(Pennisetum orientale) is a four season eye-catcher. It is reliably hardy in USDA zones 5-9. It produces smoky rose colored flower spikes (plumes) in early summer, which persist thru the winter months. Its dark green foliage begins upright in form, 2 1/2 feet tall, achieving 3 feet in height in flower. By mid- summer the grass blades cascade down, true to the name “fountain grass”.

Grow ‘Karley Rose’ in full sun or partial areas with 6 hours sunlight to maintain optimum grass form and plume color. Despite proven drought tolerance, it prefers to grow in compost rich, well-drained soil. It has a wide soil pH preference from acidic to slightly alkaline (6.2 to 7.5).

This clump growing grass is quick to establish and prospers for many years. Annual maintenance is minimal. In late fall or late winter cut back the old foliage to 3-4 inches and feed with a high nitrogen lawn grade fertilizer. Fountain grass has no serious disease or insect problems and is deer resistant and salt tolerant.

The handsome foliage and attractive flower spikes of ‘Karley Rose’ provide excellent texture and seasonal color. Use as an accent specimen or group together in mass plantings.

'Buttered Popcorn' Daylily- Performs In The Mid-South

2010-07-22T16:09:00.000-07:00

Daylily 'Buttered Popcorn' (Hemerocallis 'Buttered Popcorn') produces buttery yellow 6" flowers from late June thru mid-July. The 32-inch tall floral scapes are well branched and flowers are mildly fragrant. Bud count on each scape may average 10 or more.

This tetraploid cultivar is also well known for its incredible fall re-bloom. In the Southern Appalachian Region (zones 6-7), 'Buttered Popcorn' is rated as a better re-blooming daylily than popular favorite 'Stella de Oro'.

Daylilies require little care. They grow in almost any well-drained soil type. Daylilies grow best in full to partially sunny areas. Allow 6 hours of sunlight for high bud bloom count. Although drought tolerant, re-blooming varieties perform best with 1-inch or more of water (or rainfall) per week during the summer months.

In late fall, cutback daylilies to 3-6 inches in height. Remove the old plant debris. Daylilies possess good disease and pest resistance. Fertilize once with 10-10-10 and mulch plants in late winter or spring. Feed a second time in early June before flowering begins.

Daylilies are great additions to large containers or plant them in garden beds. The short (under 24-inch tall) daylily varieties are also utilized as ground covers along steep slopes.

'Diabolo' Ninebark as Small Patio Tree

2010-07-18T09:59:00.000-07:00

photo: 'Diabolo' ninebark trained as a small tree

I saw this idea several years ago at an Ohio nursery. Common ninebark (Physocarpus opulifolius) is basically a utility shrub, inexpensive to purchase in large quantities. This midwest native grows in almost any soil or landscape environ except shade and bog areas. Over the past decade ninebark has gone to "beauty school", and a number of new cultivars, including purple leaved 'Diabolo', are currently available.

Ninebark is a vigorous grower and possesses a unique exfoliating bark trait. In the hands of a capable pruner, ninebark can be easily shaped into a small 10-12 foot single stemmed tree. The purple 'Diabolo' foliage plus its inner light tan-colored ninebark adds up to a winning landscape combination.

I suspect that suckering at the crown will likely continue, necessitating sucker removal by a hand pruner (do not use a weed wacker) every few months. 'Diabolo' ninebark purple leaf color holds the longest under full sun and bleaches out to green by mid-summer. 'Diabolo' offers pinkish white flowers from mid-May into June, followed by red fruit clusters (seed capsules) through the summer months.

Windmill Palm

2010-07-15T19:55:00.000-07:00

Photo by Dr. Tim McDowell, East TN State University Botanist of an 8 year old windmill palm (now deceased)
Windmill Palm (Trachycarpus fortunei) is not reliably hardy in the Southern Appalachian region (zones 6-7), even when planted in an outdoor protected area. An alternative is to grow in a container for ease of moving it indoors before the cold weather in late autumn arrives. Windmill palm is hardy to +15° F.

If planted in a protected garden spot, dig a hole wide twice as wide and no deeper than it came in the nursery pot. Palms, particularly those which you are trying out, are best planted in very late May. Frequent watering is crucial for a newly-planted palm. The well-drained porous soil should not be allow to completely dry out. Windmill palm should be fed bi-monthly during the warm months with a water-soluble fertilizer applications.

Windmill palm may eventually grow from 10 - 20 feet in height. Its medium green palmate leaves are circular, increasing in diameter to approximately 3 feet after 20-30 years. The trunk is covered with dense, light brown, hair-like fibers, easily damaged, and made vulnerable to insects and fungus.

Japanese Maple Selections for Mid-South

2010-07-12T15:01:00.000-07:00

Photo: 'Sango Kaku' coral bark maple in November

Japanese maple (A. palmatum) offers a vast array of shrub and tree forms of varying heights and leaf shapes. Spring and summer leaves vary from gold, to dark green, to deep red and some color variegation and either cutleaf or dissected forms.

The dissected leaf forms of A. palmatum prefer morning sunlight and protection from winter wind and summer heat. Several hundred cultivars are available through local and mail order sources. Some popular cultivars grwon in the Southern Appalachian region (zones 6 & 7) are:
· ‘Tamuke yama’, ’Inaba Shidare’ (Red Select), and ‘Crimson Queen’ are weeping, red cutleaf forms
· ‘Viridis’- weeping green cutleaf to 20-25 feet
· ‘Seiryu’ - upright green cutleaf to 15 feet
· ‘Bloodgood’ - red palmate leaf to 20-25 feet
· ‘Heffner’s Red Select’ retain its red summer leaf color longer the popular ‘Bloodgood’
· ‘Butterflies’ - white variegated leaf to 12-14 feet
· ‘Sango Kaku' and 'Beni Kawa' – the "coral bark maples" with red twig and trunk bark from mid- fall thru late winter.

Growing Hardy Banana

2010-07-08T12:50:00.000-07:00

Hardy banana (Musa basjoo) survives winters as far north as New England and Ontario, Canada (USDA Zones 5-10). It is a herbaceous perennial which grows to 6-14' tall. Its roots, when heavily mulched, survive winter temperatures of -10 degrees F. Grow hardy banana in compost rich, well-drained soil in full sun to partial shade. Feed with a 3-6 month slow-release fertilizer supplied in early spring.

In the southern Appalachian region (USDA zones 6-7) hardy banana produces enormous 3-4 foot long leaves which gives any garden a tropical look. Give banana plants lots of space. By late summer, the large tropical leaves cast lots of cooling shade over a nearby patio or low deck . Fruit and off-white flowers are not formed because our growing period is not long enough.

If grown in containers, use a well-drained potting soil mix. Keep the container soil evenly moist, but never saturated. Reduce water and no fertilizer applications as winter approaches. In USDA Zones 5-8, store plant(s) and the container in a non-freezing area indoors over the winter months to protect the tender roots.

Plant roots become more aggressive over the years. Established plants produce numerous shoots, called “pups”. Older plants form large colonies, consuming more and more garden space each year.

Site your banana in a partially sheltered area away from high winds, which may tear the large leaves. Hardy banana has no serious insect or disease problems.

Coreopsis 'Route 66' - A Riot of Color

2010-07-05T14:32:00.000-07:00

Create a hot splash in your garden this summer. Threadleaf coreopsis (Coreopsis verticillata) ‘Route 66’ is a new selection by Itsaul Nursery in Atlanta, Georgia (USDA zone 4 to 9). Coreopsis ‘Route 66’ originated in Pennsylvania (zone 5). Perennial gardeners have been planting yellow- flowered ‘Moonbeam’ and ‘Zagreb’ cultivars for over a quarter of a century.

The 2- inch wide yellow and red splotched flowers bloom continuously from June thru August. The center red pigment seems to bleed into the yellow petals. In the autumn the red tint becomes more dominant. No two blooms are ever alike. Deadheading will extend the blooming time span into October. Foliage is green and narrow (thread-like). Plant form is upright and well branched. Route 66 grows 2 to 2 1/2 feet in height, and a few inches wider than tall.

Plant in well-drained soil in full sunlight. Route 66 is a garden performer, a low maintenance perennial to enjoy in your garden for many years ahead. Route 66 exhibits exceptional plant vigor and flower power. One year old established plants demonstrate exceptional heat, drought and cold hardiness.

"pH Nutrient Creep? -You Nailed It"

2010-07-02T14:07:00.000-07:00

Photo: Foliar iron deficiency on river birch
River birch (Betula nigra) is a popular landscape tree in the Southern Appalachian region (USDA zones 6-7). The cultivars 'Heritage' and 'Duraheat' have made a good native species even better with resistance to aphid and leafhopper insects. However, river birch demands a soil pH which is moderately acid. Why?

Iron is an important minor nutrient element. If the soil pH rises (becomes less acidic), available iron becomes less available to plants. Major landscape trees also affected by "pH nutrient creep" include favorites as pin oak, willow oak, sweetgum and littleleaf linden. An old timey recommendation was putting several nails in the bottom of the hole at planting time.

Modern day solutions include: 1. adding elemental sulfur in late fall to lower the pH and next year's new foliage should stay green all summer long; OR 2. apply iron supplying fertilizers like Ironite® or Sequestrene®, following package rates accurately; OR 3. feeding acid raising soluble fertilizers like Miracid™ or Hollytone® which contain iron.

Follow any one of these three approaches and summer color will gradually return this summer or next.

Culver's Root (Veronicastrum)

2010-06-28T14:00:00.000-07:00

Photo: new cultivar ‘Fascination’ with lavender purple flowers

Midwest native Culver’s root (Veronicastrum virginicum) starts the summer flowering season in my perennial garden. It naturally grows in open woods and meadows and thrives in fertile to moist soils. However, this deep rooted plant hasn’t complain about the current dry period in the Southern Appalachian region (USDA zones 6-7).
Culver’s root can be somewhat aggressive. Over a decade in my garden, a single plant now occupies 18 square feet. It prospers in infertile clay soil. When grown in full sun, it does not require staking. I grow it in the rear of the flower bed next to another favorite - goldenrod (Solidago spp.).
The narrow floral spikes stand 3-5 feet tall, depending on the variety. White flower spikes are most common, and attract large numbers of butterflies and bees. Flowering continues over 4 to 6 weeks, the terminal blooms first and secondary laterals in late July. Floral designers love the keeping quality of the bloom spikes and lovely narrow leaves which are arranged in whorls around the branchless stems.
Culver’s root is a low maintenance perennial. It will re-bloom if old flower spikes are deadheaded. There are no disease or insect problems.

Agapanthus- Hardiness Issues

2010-06-25T10:31:00.000-07:00

Lovely agapanthus (Lily of the Nile) is native to South Africa and is not reliably hardy in the Southern Appalachian region (zones 6 – 7). Many small tubular flowers comprise each ball -shaped (umbel) flower cluster. Tall sturdy floral scapes rise 1 to 4 feet in height, blooming from late spring into late summer depending on the cultivar. Many cultivars are available in shades of blue, purple and white.
In this region, agapanthus may be dependably grown in outdoor landscape planters which are brought inside in the fall. Agapanthus has multiple cultural issues: cold hardiness, wet wintry soils and hungry voles. Further south in zone 7-b, the crown may be covered over with several inches of leaves or mulch in late fall. The mulch is removed once the threat of spring frost has passed.
Agapanthus produces attractive glossy, strap-like green leaves, which grow from its fleshy tuberous roots. It is propagated by division of the root clumps immediately after flowering. Divide vigorous clumps every 2 to 3 years in early spring.
Agapanthus prefers a well-drained, fertile, slightly acidic soil. Locate the plant in a warm, sheltered spot under partial sun. Space plants 24 inches apart with its shallow surface roots barely visible on the ground.
Don’t permit agapanthus to dry out. Weekly watering encourages a deep extensive root system. Soggy soil is never good; the leaf tips turn yellow in a waterlogged soil.
Agapanthus requires light constant feeding in the spring and summer months using either water-soluble or slow release fertilizer with a 10-20-20 ratio. In the fall stop feeding and reduce watering to induce plant dormancy.
Pruning is done sparingly, usually to remove damaged or dead foliage before new leaves emerge in the spring.
Mealybug , red spider mite, and voles may become significant pest/critter problems.

"My Maple Tree Is Being Invaded"

2010-06-21T11:25:00.000-07:00

photo: Dr. Alan Windham, UT Plant Pathologist

The following is a real query sent to an Extension agent over the phone: “I have thousands of insects on 8 of my 10 maple trees. I fear they will kill my trees, one has already died. The insects huddle together. I am not positive they have wings, they may, but refuse to fly. Their antenna are twice as long as their body; 6 legs; body is 1/4” long, blackish, the body tapers to a pointed rear end. I see multiple groups on my tree branches. Smaller, shorter ones have white lines across body. They are the younger ones.
Barklice also called psocids (Order Psocoptera feed on mold/fungi etc. on the bark). They are harmless and tend to aggregate. There are immatures (without wings) and adult (winged) present. The photo shows the winged barklice adults.
Lesson learned: not all insects are harmful, ready to injure your garden plants. Are you curious what killed the homeowner's other maple tree last year? I am too, but he cut it down before anyone could diagnose it.
Contact your local county Extension office for gardening assistance.

New Hardier Gardenias

2010-06-18T19:23:00.000-07:00

Old fashioned gardenias or cape jasmines (Gardenia jasminoides) are reliably hardy in USDA zones 7-b and 8. Plants require immediate protection when the outdoor temperatures dip below 15 to 20 degrees.

The new hardier cultivars are compact growers, 2-4 feet tall and 3-4 feet wide. ‘Frost Proof’, Crown Jewel™, and Heaven Scent™ are three promising hardy cultivars to try in USDA zone 7-a. All three strut great thick, high gloss, dark green foliage.

Choose a garden location with good air circulation. Morning sunlight and afternoon shade is the rule. Plant gardenias in a well-drained acidic soil, and generously amended with compost. Water plants when dry and never overwater them. Acute leaf drop occurs in poorly drained soil. Fertilize once a year after the heaviest blooming cycle in June has past.

Fully capture gardenia's fragrance by planting in a garden spot or a container nearby a deck or patio. Individual blossoms generally last a few days. Flower loss may be rapid following a wind and rain storm.

Prune gardenias is immediately after blooming in early July. Remove all dead or unsightly shoots anytime you see them. Additional scattered blooms may occur anytime during the growing season. Late pruning should be avoided in the fall as next year's flower buds are being set.

White flies and flower thrips are major nemesis of gardenias. Bayer Advanced Tree and Shrub™ (soil drench) and horticultural oil (spray) should clean up most pest problems. Always read the pesticide label before using!

Smaller Southern Magnolias

2010-06-13T18:56:00.000-07:00

The grand Southern magnolia (Magnolia grandiflora) thrives here in the southern Appalachian region and along the Eastern seaboard as far north as Boston (USDA zones 6-9). Most homeowners do not have room enough to grow this 60-70 foot arboreal aristocrat.

Compact forms are available that need less than half the space. The ivory white flowers are fragrant and 25% smaller than full sized trees. Blooms open individually, not all at once, from late May thru the summer months. The most popular compact cultivar is ‘Little Gem’. It grows to a height and width of 40 x 35 feet in 25-30 years. Others include ‘Hasse’ (45 x 20 feet) and Teddy Bear® (30? x 20 feet).

The newest introduction is ‘Kay Parris’ with exquisite polished green wavy leaves and mahogany brown beneath. The parents of ‘Kay Parris’ are 'Little Gem’ and 'Bracken’s Brown Beauty’. As a young tree, 'Kay Parris' exhibits an upright, narrow (columnar) form, rating it a great evergreen tree for a small garden space.

Southern magnolia is planted from late winter through early fall in well-drained, organically amended soil in a full to partially (6 hours minimum) sunny area. Tree rarely has disease and insect issues.

Squash Vine Borer

2010-06-10T09:02:00.000-07:00

photo credit: Dr. Alan Windham, Univ. of TN Extension Plant Pathologist

Squash vine borer (SVB) damages squash, gourds, and pumpkins. Cucumbers and melons are usually not attacked by the SVB.

The adult SVB is a clear-winged moth. The 1 inch long adult moth is commonly mistaken for a wasp. Its abdomen is ringed with orange and black. Females lay oval brownish eggs on plants in late May or early June. The borers tunnel into stems near the soil and feed on the plant. Excrement is visible near points of entry on the stem when larvae are feeding. Heavy feeding causes the infested vine(s) to wilt and die.

Select a variety which is SVB tolerant. Also, cover emerging plants with row covers to reduce possible damage. Remove row covers when the plants begin to bloom to permit insect pollination. Stagger new plantings every 2-3 weeks to avoid SVB populations.

Some gardeners cover the main stem with pantyhose to prevent egg laying by adults. Infested stems can be split and larvae removed. Add a spade-full of moist soil over damaged stems to encourage new root growth. Insecticides must be applied prior to borers entering into the stem.

Insecticides containing carbaryl, bifenthrin, spinosad, or permethrin are effective against SVB. Apply an insecticide every 5-7 days. Please read the pesticide label before applying.

Vitex 'Shoal Creek'

2010-06-09T14:27:00.000-07:00

Chastetree (Vitex agnus-castus) is an 8-10 foot deciduous shrub or 12-15 foot tall small tree (hardiness zone 6-b thru 8). Branching habit is dense and vase-shaped (upright). It blooms over most of the summer, from June thru late August. Its 12-18 inch long blue-violet flower spikes exude a slight herbal fragrance.

‘Shoal Creek’ is a leading cultivar. Cold hardiness appears better than most, although this has yet to be proven. The finger-like compound leaves are covered with pubescent hairs. Summer foliage color is grey-green, with a faint bluish cast more visible in May and June. Its disease resistant foliage and butterfly magnetism rates this vitex in a class on its own. Foliage is highly deer resistant.

Stem die-back may occur in a cold winter, but this fast grower recovers rapidly. Since flowering occurs on new growth, prune off all dead, injured and crowded branches before the start of May. Vitex prefers full sun, but will tolerate part sun. Plant in a loose, well-drained soil and keep adequately watered during the first year. Afterwards, vitex possesses very good drought tolerance.

Northern Catalpa

2010-06-08T09:39:00.000-07:00

Northern catalpa or Indian cigar tree (Catalpa speciosa) has enormous presence in any landscape setting. Finding a 70 - 80 foot tree with a massive trunk and thick sinuous limbs is not uncommon from Ohio south thru Tennessee. In summer its huge heart –shaped, pale green leaves may be easily reach 8 - 12 inches long and wide. Birds often seek shelter under the foliage canopy.

Catalpa offers a spectacular flower display lasting two weeks or more in May. The tree is common along roadsides, particularly in bottomlands, often growing in poor soil. Numerous two- inch long white flowers are borne on large terminal spikes, many unfortunately hidden beneath the enormous catalpa leaves. Each flower has small gold spots within its frilly edged corolla. Narrow cylindrical cigar fruits, 8 - 15 inches in length are easily visible in the fall and winter months.

Catalpa trees are often visited by the catalpa sphinx moth whose larvae (caterpillars) are prized by fishermen for bait. Hummingbirds are a major pollinator, attracted to the floral nectar.

This fast growing tree finds only limited value in a residential neighborhood due to its coarse leaf texture. The brittleness of small limbs demands almost constant clean-up.

Indian Pink is a Summer Sizzler

2010-06-06T15:59:00.000-07:00

Indian pink (Spigelia marilandica) is a strikingly beautiful native wildflower here in the southern Appalachian region (USDA zone 6 -7). Beginning in late May, bright red tubular flowers flare open, crowned by five sharply pointed pale yellow reflexed lobes (see photo).

Indian pink prospers around rich moist open woodland areas. The well-drained soil should have a pH range between 6.5 to 7.0. Generously amend a partially sunny site with compost or peat to stimulate plant vigor and repeat flowering. Healthy plants grow 12-18 inches tall. Spigelia leaves attach directly to the main stem without petioles.

Indian pink is slow growing at first, taking two to three years to reach maximum floral potential. Planting five or more in a clump creates a showier display. Eventually, a healthy grouping will colonize. Bloom time is lengthened by swift removal of the old spent flowers.

Indian pink often blooms for a brief second interval in late summer when soil moisture is plentiful. Plant debris mostly disappears before winter sets in. The brightly colored flowers attract numerous pollinating insects and hummingbirds. No disease and pest problems are observed.

Hardy Rosemary

2010-05-30T15:52:00.000-07:00

Rosemary (Rosmarinus officinalis) ‘Arp’ is winter hardy in southern Appalachian (USDA hardiness zones 6-b and 7-a) gardens for two decades , including some very cold winters. Other rosemary cultivars which have succeeded include ‘Athens Blue Spires’, ‘Hardy Hill’, and ‘Salem’.

Locate a site with a “micro-climate" advantage such as next to a driveway or along the southside of a red brick home or a dark colored garage wall. Here winter temperatures vary by a few degrees warmer. Dark asphalt pavement absorbs and retains heat. Next to large bodies of water, such as a swimming pool and a water garden, may also be slightly warmer in the winter.

Plant rosemary in well-drained soil and in full direct sunlight. With rosemary and other semi-tender herbs, winter kill may also be caused by wet, soggy soil rather than cold.

‘Arp’ matures a handsome woody shrub with fine textured foliage. It grows 3-4 feet tall and wide, and blooms in early spring. The blue flowers are small and attract lots of insect activity.

Dreaded Rose Rosette Disease

2010-05-24T07:56:00.000-07:00

No rose is resistant to this deadly virus disease. Symptoms of rose rosette disease (photo) vary greatly from the species or cultivar planted. Leaves may be small, distorted, and exhibit a conspicuous red pigmentation. Diseased canes may also be noticeably thicker than others around them, and/or may grow in a spiral pattern.

Multi-flora roses, a noxious shrubby weed, are most susceptible and often are first to contract the disease. Very small eriophyid mites transmit rose rosette disease by feeding off the plants which are already infected. Mites transmit the virus to healthy roses nearby. Control measures must be rapid and decisive.

Insect spraying will help. Spray roses with Sevin (carbaryl) insecticide for partial control of the eriophyid mite. Eliminate multi-floral roses within 300 feet from any rose plantings, preferably from all surrounding yards and gardens.

Prune out all diseased and suspected canes. Remove all prunings immediately from the property. If symptoms reappear on new re-growth canes, remove the bush from the property. When planting roses, space them far enough apart that foliage does not touch neighboring plants.

Lovely Lavender

2010-05-22T17:39:00.000-07:00

photo: 'Munstead' lavender

Lavender is a hardy shrub that thrives in dry alkaline soil. Lavender is commonly used as a food seasoning, a culinary substitute for rosemary. Dried flowers are crafted into table arrangements and lavender fragrance is captured in sachets and potpourris. Lavender is used to store clothes as a moth repellent. Some people store some under a pillow as a sleep aid, a form of “aromatherapy”. Bees produce a high-quality honey from the flower nectar.

There are two kinds of lavender. The shorter-growing cultivars of English lavender (Lavandula angustifolia) like ‘Munstead’, ‘Hidcote’, and ‘Lady Lavender’, flower in mid-May for one month. When cutback, English lavender blooms again in August. The taller more vigorous French lavender (recommend cultivars ‘Provenance’, ‘Grosso’ and ‘Super’) flowers only once in late June. For lavender oil production, I recommend ‘Super’.

Lavender is only successful planted in soil that is exceptionally well drained. An ideal soil pH range is 6.5 - 7.2. Grow on raised mounds and space plants 3 feet apart in the row and 6-8 feet in the row, if grown commercially. Other than for harvesting, prune plants back one-third in a ball shape in September. Lavender has very few disease and pests problems and possesses high drought tolerance.

FireBlight on Apples and Pears

2010-05-20T08:13:00.000-07:00

Fireblight is a serious bacterial disease that afflicts apple and pear trees. Fireblight may appear in two distinct forms. From April to early May flowers and fruit clusters may blacken (die). From May to mid-June a more serious symptom (photo) is sudden dieback, almost overnight, of branch tips . Leaves appear as if someone had poured gasoline over the tree and torched it. Infected branch tips may also look curled, as a so-called "shepherd's crook".

To prevent the spread of fireblight, prune off all diseased wood, cutting back 6 - 8 inches into adjacent healthy shoots. Pruning is done either when first seen or when the tree is dormant. Disinfect the pruning shears after each cut, dipping the blades into either rubbing alcohol or 20% bleach to water solution. Remove all diseased prunings from the property. Do not compost.

When planning an apple or pear home orchard, avoid planting very susceptible varieties such as 'Lodi', ‘Gala’, ‘Jonathan’, ‘Rome’, and ‘ Yellow Transparent'. Among pear varieties, ‘Bartlett’, D’Anjou’, ‘Bosc’ and ‘Clapps Favorite’ are most susceptible, and ‘Moonglow’, ‘Maxine’, ‘Magness’, and ‘Seckel’ are moderately resistant to fireblight. Most Asian pear varieties are very susceptible.

No-Spray Shrub Roses

2010-05-17T10:46:00.000-07:00

Photo: Carefree Sunshine Rose at UT Gardens in Knoxville, TN
Over the past decade the Knockout®, Carefree® and Home Run® series of shrub roses have altered the appearance of residential and commercial properties. From 2006 -08, no-spray rose trial was conducted at two University of Tennessee Research and Education Centers in Jackson and Crossville, TN and the USDA Horticultural Research Lab in Poplar, MS.
Over 135 cultivars were evaluated. "The ultimate disease test for roses is to test them south of the Mason-Dixon line where disease pressure is highest", according to Dr. Mark Windham, UT Research Pathologist.

Shrub Roses Resistant (R) or Moderately Resistant (MR) to Black Spot and Cercospora Leaf Spot:
Carefree Sunshine (MR) - F
‘Fiesta’ (MR)
‘Golden Eye’ (R]
‘Hansa’ (R) - F
‘Homerun’ (MR)
Knockout Rose (R)
‘My Girl’ (R) - F
‘My Hero’ (MR)
‘Palmengarten Frankfurt’ (MR) - F
Pink Knockout (R)
‘Super Hero’ (MR)
’Wild Spice’ (MR) - F
‘Wild Thing’ (MR)
‘Wildberry Breeze’ (R) - F
F indicates rose is fragrant

Best of the Climbing Roses So Far-- 'White Dawn'

2010-05-15T17:50:00.000-07:00

Since its introduction in the rose world over 60 years ago, 'White Dawn' has proven to be a top garden performer among climbing roses. The dark green, glossy foliage is very blackspot disease resistant. This very vigorous climber (hardiness zone 5 – 9) grows to 12 to 20 feet. Pure white double flowers are medium-sized (2-1/2" to 3"). 'White Dawn' tolerates poor soils if drainage is good. It blooms best in a bright sunny spot.

'White Dawn begins blooming in mid-May in the southern Appalachian region (Zone 6-b to 7-a) and repeats, off and on, through the rest of the growing year. Feed roses starting in early April and monthly to early September with Miracle-Gro®, Schultz®, or equivalent water soluble rose food @ 1 tablespoon per gallon.

Prune climbing roses in late winter (March) when new growth begins. On young climbers, simply remove all diseased, dead and tall nuisance canes. On older climbers, cutback the oldest rambling canes, favoring strong healthy one-year shoots which produce most of the rose blooms in May.

‘White Dawn’ is the first climbing rose to earn the University of Tennessee “No Spray” designation.

Yellowwood --"In The On-Year"

2010-05-14T08:25:00.000-07:00

American yellowwood (Cladrastis kentukea) is a medium-sized flowering landscape tree. Generally, from early to late May, the beautiful yellowwood tree blooms in the Southern Appalachian region (USDA zone 6-b to 7-a). Twelve to fourteen inch long white pea-shaped flower panicles drape from the tips of tree branches.

I know the location of a dozen yellowwood trees in northeastern TN and 11 of 12 did not bloom in 2009. The 12th tree bloomed sparsely. In 2010 all trees are exceptionally beautiful in full bloom this week and last. So far, plant scientists are at a loss predicting the “on” and “off” annual flowering pattern.

Yellowwood may bloom 2 to 3 consecutive years and not flower again for the 1-2 years. A complex of environmental and physiological factors may be involved. The weather history over the past decade in the Southern Appalachian region has included several abnormally hot, dry summers and mild winter temps. The 2009 summer was unusually cool and moist followed by a longer cold winter.

A second theory, called "biennial bearing", states that if a tree sets an unusually heavy seed load in the summer, few to no flowers are initiated for the following spring.

The flowering trigger for yellowwood tree is not understood. Whether in flower or not, yellowwood makes a fine addition to any landscape.

Growing Tomatoes in Containers

2010-05-10T08:25:00.000-07:00

Tomato Fest V in August 2009 in Kingsport, TN

Apartment renters and townhouse and condominium owners till the soil in containers on their patio and deck. For containers the shorter growing determinate type tomatoes are a better choice. Spread out the harvest interval, by not planting all your tomatoes at one time. Start your last tomatoes from seed for June planting and harvest beginning in late September and October.

Container grown tomatoes need a deep container- at least 16 to 18 inches tall. A 5- gallon (or larger) pail or pot works well. Drill out several 1- inch wide drainage holes and add a few rocks in the bottom for ballast. Plant in a good growing media and add some inorganic fertilizer or organic bone and blood meal to increase fertility. Container-grown plants require more frequent fertilization than field-grown, as there’s less soil from which to obtain nutrients. For water soluble fertilizers, apply every two weeks.

Here are some good varieties to try. The yield will vary with the variety:
• Slicers
– Bush Early Girl
– Bushsteak Hybrid
– Spring Giant
– Better Boy
– Jetstar
– Bush Celebrity
– Mountain Fresh Plus VFFN
– Super Bush
– Saladette (Roma type)

• Cherry
– Golden Nugget
– Sweet 100 Patio
– Tiny Tim
– Patio
– Supersweet 100
– Sun Gold

Alternatives to Italian Cypress

2010-05-07T07:58:00.001-07:00

'Sky Pencil' Holly at Chanticleer Gardens in Wayne, PA

Those of us who live north of Atlanta, GA (USDA zone 7-b) can not enjoy Italian cypress (Cupressus sempervirens), which are not hardy in most of the Southern Appalachian region (zone 6-a to 7-a). If you are designing a Mediterranean look in your garden, choose among select cultivars of these columnar evergreen shrubs:
Japanese holly (Ilex crenata) 'Sky Pencil'
Upright boxwood (Buxus sempervirens) 'Dee Runk' and 'Pyramidalis'
Red cedar (Juniperus virginiana) 'Taylor', 'Brodie', 'Blue Arrow', 'Idyllwild'

Eastern arborvitae (Thuja occidentalis) 'Techny', 'Pyramidalis'

Common juniper (Juniperus communis) 'Pencil Point'
Alaskan cedar (Chamaecyparis nootkatensis) 'Green Arrow', 'Van den Akker'

Hinoki cypress (Chamaecyparis obtusa 'Vokel's Upright')

Arizona cypress (Cupressus glabra) 'Limelight', 'Silver Smoke'

Rocky Mountain juniper (Juniperus scopulorum) 'Skyrocket', 'Moonglow' -- needle foliage breaks down over time in warm 6-b to 7-a summers. Better in zone 6-a and further north.

‘Upright Japanese barberry (Berberis thunbergi) 'Helmond Pillar' – deciduous

Likely, you may be challenged by a lack of availability of several of these fabulous conifers at local garden centers. Often, an internet source becomes your best option for purchasing one or more.

Growing Blueberries

2010-05-05T14:27:00.000-07:00

Both the highbush and rabbiteye blueberry (Vaccinium spp.) are hardy in the Southern Appalachian region (zone 6-b to 7-a). A hot summer is a nemesis for highbush and an extremely cold winter limits where you can grow rabbiteye within zone 6-b.

Blueberry bushes grow 8-15-feet tall, requiring annual pruning. Its dark green foliage turns brilliant red in the fall. Pale pink flowers appear in the spring followed by the berries which start out as pale-green (pictured) and ripen to dark bluish-purple.

Blueberries are very shallow rooted and must be irrigated regularly during their growing season.

Space blueberry bushes 5 to 7-feet apart with rows 8-feet apart. Mulch with a black fabric matted base and cover with an additional 3-4 inches of sawdust, wood chips or pine needles. For info. on garden soil prep, see blog dated 4/30/10.

Use an organically-based, slow release fertilizer composed of sulfur-coated prills. A newly blueberry plant starts with one ounce of ammonium sulfate to a maximum of 8 ounces of ammonium sulfate for a mature bush per year. Bushes reach full production in 6-10 years.

For highbush blueberries (I recommend 'Duke', 'Bluecrop' and 'Blueray' cultivars) are harvested starting from mid- June thru late July and rabbiteye ('Tifblue' and 'Premier') are ready from mid- July thru September.

Birds love ripe blueberries as much as people do. Cover your bushes with netting or plan on sleeping outside when harvest time.

Hybrid Decidous Azaleas Brighten The May Garden

2010-05-03T05:13:00.000-07:00

The bright reds, oranges and yellows of the hybrid deciduous azaleas (Rhododendron spp.) are lovely among tall shade trees which protect them from the harsh afternoon sunlight of summer. Because their bloodline is from our native piedmont azalea species in the Eastern U.S., hybrid deciduous cultivars possess exceptional disease and insect resistance rarely seen in the more popular evergreen forms.
This past weekend I saw this lemon yellow gem (pictured) in a friend's garden in Lenoir, NC called 'Sunny Side Up'. The very popular 'Gibraltar' (bright orange) has been blooming over the past 15 years blooming in my northeast TN garden next to 'Gold Finch' (yellow-gold).
Annual care is very minimal: Feed once after flowering with any slow release azalea or evergreen fertilizer. To invigorate the azalea, prune back one or two very tall woody branches near the base of the shrub to promote new shoot growth. The new branches will likely flower next spring and many more thereafter. One year established shrubs are also very drought tolerant.

New Blueberry Planting Require One Year Soil Prep

2010-04-30T06:18:00.000-07:00

Fresh blueberries a few more weeks away from harvest

Blueberries are the easiest fruit crop to grow. Blueberries have few disease and insect problems. Birds become a significant problem as harvest time approaches, from mid-June through September. Blueberry culture is unique as the ideal soil pH range is 4.8 - 5.2. You should spend a year to lower the soil pH and raise the organic level to 3% and higher before planting blueberries.

Select a sunny location preferably with an east or northern exposure. Reduce the weed population by applying monthly applications of Round-up™ (glyphosate) herbicide over the planned blueberry site from April thru September. Have the soil in the blueberry patch analyzed. Follow the instructions on the soil test report, applying 0.2 lbs of elemental sulfur per 100 square feet for each 0.1 pH unit adjustment.

Sample calculation: you have cleared a strip of 6 feet wide by 16 feet long (approximately 100 square feet) for 3 plants. Your soil test recommends lowering the pH by 12 units (measured in tenths), so multiply .2 pounds sulfur x 12 units. The answer is 2.4 lbs of sulfur per 100 square feet. After 6 months, check the soil pH again to determine if you need add more sulfur.

Keep Your Eye on Red Buckeye

2010-04-28T09:10:00.000-07:00

Red buckeye (Aesculus pavia) is the perfect small tree for an urban landscape. This native tree/large shrub flowers young in a full or part sun location. Numerous 5- to 9- inch long flower panicles are positioned on the tips of branches as decorative red candles in late April and May here in the southern Appalachian region (zones 6 thru 8).

Flowers open just before or after the leaves begin to emerge. Flower color on individual trees may vary from dark pink to scarlet red. Most trees are at their showiest in late April and early May. Hummingbirds arrive to pollinate the 1 ½ inch tubular blooms.

Lustrous palmately compound leaves dress the branches in rich green over the spring and early summer months. Disease and insect problems prove of little consequence, except that the greenery becomes scorched and spotted by late summer. Leaves drop prematurely in September, far ahead of other landscape trees.

The Fear of Trees

2010-04-28T06:51:00.000-07:00

Dendrophobia is the psychological fear of trees. At recent Earth Day gatherings we learn of the importance of trees in the environment. Most of us know that tree topping is bad, yet the practice continues. Large trees are butchered (not pruned) every year.

Some tree topping stems from a “lemming mentality”, that is, “I did it because my neighbor did it”. When asked if the neighbor was very intelligent, most replied that they rarely sought their advice on anything.

Other folks need to control nature and their surroundings. They love large trees, but fear the damage that fallen limbs might wreak on home and property. Property owners living in areas recently hit with terrible storm are more prone to remove large trees or heavily prune them.

Power tools in the hands of inexperienced property owners cause additional damage to large trees. It’s called "chain saw massacre", removing more than originally planned.

Finally, a local certified arborist told me: “People living in a neighborhood with topped or severely pruned trees felt cheated when their tree was properly pruned. They paid more for removing less, more time and skill involved to do it right.”

Carolina All-Spice Sweetshrub Or Bubbybush

2010-04-24T17:43:00.000-07:00

What's in a name? Sweetshrub (Calycanthus floridus) is one of our finest native shrubs. Its waxy, reddish brown flowers emit an enticing fruity fragrance. The 2" wide flowers bloom starting in late April, and sporadically June through August.

Many gardeners in the southern Appalachians (plant hardiness zone 6 -8) call it “bubbybush” or “sweet bubby”. In the 1800's, long before deodorants, women used the fragrant flower as a perfume to mask body odor. They would hide the tough, almost indestructible flowers under their dresses, in their pockets, even pin them on their clothes.

Sweet shrub is easy to grow. Plant in fertile, well-drained garden soil and in sunny to partly shaded landscape. It flowers best in full sun and stay dense and tight. The beautiful deep green leaves measure 5-6" long, ovate, and exhibit a nice yellow fall color and persist into November. The large, 'urn-shaped' fruits mature in October.

The cultivar ‘Athens’ has yellow fragrant flowers. New Asian/American hybrids from the North Carolina State University’s plant breeding program are ‘Hartledge Wine’ (red, non-fragrant flowers) and most recent introduction ‘Venus’ (creamy white, fragrant flowers).

Try 'Fireworks' Gomphrena in Your Garden

2010-04-16T19:26:00.000-07:00

'Fireworks' gomphrena was a sensation in the University of Tennessee Gardens at both the Knoxville and Jackson locations in 2009. Gomphrena (globe amaranth) is a great summer annual that asks for very little care. It is heat, humidity and drought tolerant. Gomphrena hold up to the wind, blooming from day of planting in May (after danger of spring frost has passed) until first hard frost in autumn. No bug or disease touches them.

By fall most gomphrena cultivars grow 18 inches to 2 feet in height and 12-15 inches in width. Add another 12 inches for more the vigorous 'Fireworks'. Can't find 'Fireworks', try another cultivar favorite- 'Strawberry Fields'. Gomphrena attracts large numbers of butterflies and are great as cut and/or dried flowers.

Buy plants at local, independently-owned garden centers. Generally, "big box store" garden centers carry more common summer annuals and not gomphrenas.

The Best of the Coralbells- So Far!

2010-04-11T16:13:00.000-07:00

Photo: Heuchera villosa natural purple leaved form

The Heuchera x villosa coralbell revolution has been upon us for nearly a decade. Many new hybrid coralbells have been introduced. This southern Appalachian native coralbell exhibits exceptional heat, humidity and drought tolerance. You find hairy alumroot growing in dry shade and partially sunny areas.

This is a report card on the hairy alumroot hybrid cultivars. Listening to other gardeners and observing their performance in my garden, 'Mocha' (dark coffee colored foliage), 'Citronelle' (bright yellow) and 'Caramel’ (dark peachy yellow), have earned my highest recommendations among the colorful large foliage types.

I continue to watch 'Tiramisu', with its medium-sized, yellow with red splotched leaves. It has yet to impress me. However, gardening friends urge me to wait another year "before throwing in the trowel".

I also grow the pale green leaf, mid-summer blooming 'Autumn Bride'. A cloud of tiny white flowers hovers over the plant foliage in August. I see it used en masse as a late summer bedding plant in public gardens around the Philadelphia, PA area.

Spring Lawn Care Tips

2010-04-09T07:54:00.000-07:00

April is time for a minor lawn renovation. All lawn chores should be completed before April 18th, here in the Southern Appalachian region (USDA zones 6a – 7a). If you are planning a major lawn renovation, hold off until September.

Following a rough winter, fertilizing is a positive first step for rapid green recovery and filling in dead spots. Steps for over-seeding small dead areas: 1) light soil tilling with a rake, 2) fertilizing, and 3) seeding.

Over the lawn, apply a crabgrass preventative and again 3 months later (early July). Timing is crucial. When yellow flowering forsythia is passed blooming, crabgrass seedlings have germinated and most preventatives don’t work. Do not apply a crabgrass preventative to recently seeded areas.

Dandelion, henbit, chickweed, wild garlic and other broadleaf weeds are sprayed on non-windy days. Choose a day when air temperatures remain above 60°F for 6 hours or more.

Chart your annual mowing height through the year: first mowing at 1 ½ inches high; after first cut at 2 ½ inches until Memorial Day; during summer at 3 inches; and after Labor Day, back to 2 ½ inches.

Eastern Tent Caterpillar (crabapple, cherry, peach)

2010-04-08T13:39:00.000-07:00

photo credit: Dr. Frank Hale, Entomologist, University of Tennessee
The Eastern tent caterpillar is frequently the first insect that I receive calls about in the spring. Eggs overwinter on wild cherry trees and move on long silken treads to tasty landscape tree foliage nearby. Larvae and caterpillars consume lots of leafy matter over the next month.

Dirty white webs form in limb crotches beginning in late March when wild cherry leaves are developing. Larvae leave the web on warm sunny days to consume leaves of ornamental crabapple, peach and cherry. They remain in the web during cloudy or rainy weather.

Large landscape trees are damaged temporarily, and new foliage grows back rapidly. However, newly planted or young trees may lose most of their 1-2 year old foliage and have no reserves to grow new shoots.

In March and April, many different insecticides are labeled including horticultural oil, Sevin (Carbaryl), Bt (Dipel), Orthene, Malathion, and insecticidal soap. Always read the pesticide label for all precautions. For example, the label on Orthene states “may cause foliar injury to flowering crabapples”.

Awesome Ornamental Peach

2010-04-07T08:25:00.000-07:00

Photo is an 18- year old ornamental peach tree in Columbia, Tennessee. This tree blooms with 4 different colors bright pink, pink, peppermint, white each year. The tree is full of bloom and obviously well-pruned and cared for.

It may have been a "5 in 1" grafted tree that the home gardener purchased years ago. Ornamental peach is very challenging, susceptible to numerous diseases and insect pests. I congratulate the homeowner for keeping the tree healthy all these years.

Winter Hardy Camellias

2010-04-06T07:46:00.000-07:00

pictured: 'April Remembered'

Growing camellias in the Southern Appalachian region (USDA zone 6-a) is no longer a dream. As many as 40 cultivars of winter hardy camellias to -15 °F are now available. Flower colors range from white, many shades from pink, and red. Hardy cultivars possess big bloom size, long flowering period (fall or spring), and lustrous evergreen foliage.

Start with these outstanding cultivars. For spring blooming, plant ‘Pink Icicle’ (pink semi-double), ‘April Tryst’ (dark red anemone) and ‘April Remembered’ (pink semi-double). Dependable in the fall garden are ‘Winter’s Star’ (pale pink single) and ‘Winter’s Interlude’ (pink anemone).

The culture of camellias is similar to azaleas, rhododendrons and hollies. Plant them on the east or north side of your home or nearby large shade trees, protected from direct summer sunlight and drying winter winds.

Add generous amounts of organic compost, leaf mold or sphagnum peat to maintain an acidic soil pH. Feed shrubs every two months in spring and summer, using either water-soluble Miracle Gro™ or Schultz™ brand fertilizer.

Established shrubs are very drought tolerant after two years, needing water when rainfall is very low. Camellias enjoy relief from most pest problems that plague them further south.

Golden Hakonegrass Lights Up The Shade Garden

2010-03-28T17:26:00.000-07:00

Light up dark areas in your shade garden with this wonderful golden ornamental grass from Japan. Golden hakonegrass (Hakonechloa macra 'Aureola') grows 12-18 inches tall and 18-24 inches wide with a mounding cascading form.
Very thin green stripes (veins) flow the length of the ½ inch wide golden leaf blade. The cool nights in the fall adds a pink to reddish tinge to the blades before all dies back for a long winter’s nap. Tiny, relatively inconspicuous, floral spikes appear for a short time in late summer.
Golden hakone prospers in moist humus-rich, well-drained soil. Contrarily, it grows poorly in compact heavy clay soils. Hakone prefers a partially shaded garden spot, receiving 2 hours of early morning or 1/2 day of dappled sunlight.
Golden hakone grows slowly, spreading by stolons and rarely trespasses spaces occupied by neighboring hosta, astilbe, heuchera and other companions in the shade garden.
Golden hakone is rarely bothered by disease or insect pests and is not troubled by deer. 'Aureola' hakone grass was selected the Perennial Plant of the Year in 2009.

Viburnums for Privacy Screening

2010-03-27T10:06:00.001-07:00

photo: the clean summer foliage of 'Allegheny' viburnum

Must you plant an evergreen hedge when a semi-evergreen flowering shrub is fine for the task?

Leatherleaf viburnum hybrid cultivars 'Allegheny' and 'Willowwood' are 60% evergreen, dropping their foliage very late in autumn in U.S.D.A. zones 6 and 7-a. 'Willowwood is preferred over 'Allegheny' in areas of zone 6 and 7 where powdery mildew disease may be a problem.

Prague viburnum (Viburnum pragense) is the only "true" evergreen viburnum. It possesses lustrous dark green foliage year-round and grows to 9-10 feet. Its height is tall enough to become a beautiful privacy screen and noise barrier from the neighbors and traffic.

All three viburnums are excellent growers. They have a distinct advantage over most conifer species used in privacy screening. These lovely viburnums flower in late spring and early summer, something the conifers don't offer.

When to Prune Flowering Shrubs

2010-03-26T07:08:00.000-07:00

photo: Weigela 'Wine and Roses'

Prune spring flowering shrubs and trees immediately within one month after flowering. These plants set their flower buds on last summer's woody shoots. Common shrub examples include forsythia, lilac, weigela, mockorange, loropetalum, honeysuckle, and many viburnum species.
Summer-flowering plants set their flower buds on spring wood (this year) when they bloom. They are pruned in late summer into early fall (after flowering). You may also wait until late winter into early spring before shrubs leaf out. Some examples are crape myrtles, althea (Rose of Sharon), chaste tree (vitex) and most hydrangeas.
Other tips: remove all dead, diseased, and damaged wood anytime of year. If scale insects are present, remove the worst infested shoots, reducing the need for pesticide spraying.
Prune off weak spindly wood if it takes away from the desired shape or form of the shrub.
Finally, you can reduce shrub height by pruning off the branch(es) at point of origin, near the ground around the base of the shrub.

Lo and Behold 'Blue Chip' Buddleia is a Winner

2010-03-21T17:51:00.000-07:00

photo taken at JC Raulston Arboretum in June 2009

Lo & Behold® ‘Blue Chip’ is a very dwarf butterfly bush (buddleia) for the summer garden. Take advantage of its compact 3 x 4 foot height and width by planting it in the garden or in a container on a sunny patio deck or patio by itself . In large containers mix in shorter growing summer annuals such as trailing petunia, scaevola or alternanthera.

Lo & Behold® ‘Blue Chip’ maintains its clean growing habit all season long. Gardeners with limited space can attract butterflies and hummingbirds to their garden with this colorful buddleia. It produces loads of fragrant blue flowers which bloom continuously. It thrives in the summer heat and humidity and the foliage stays blemish-free.

'Blue Chip' is non-invasive. It's self-cleaning and will bloom from mid-summer to frost without deadheading. Each proceeding spring, you won’t need to drastically prune 'Blue Chip' as you would the larger growing buddleia varieties. Plants are deer resistant and drought tolerant.
‘Blue Chip’ was still blooming in my Southern Appalachian garden in late October .

Best of Perennial Veronicas for Gardens

2010-03-17T13:30:00.000-07:00

photo: Veronica spicata 'Royal Candles' (not evaluated in CBG study)

Chicago Botanic Garden (CBG) has published the results of a 10-year study of speedwells (Veronica and Veronicastrum) in its 33rd issue of Plant Evaluation Notes, “A Comparative Study of Veronica and Veronicastrum".

Seven speedwells received good-excellent ratings for their overall performance, including Veronica ‘Fairytale’, V. ‘Giles Van Hees’, V. austriaca ‘Ionian Skies’, V. longifolia ‘Blue John’, V. spicata ‘Baby Doll’, V. spicata ‘Ulster Blue Dwarf’, and V. wormskjoldii. These top-rated speedwells exhibited strong growing and excellent flower production throughout the evaluation period. The lack of any serious pest or disease problems, along with good winter survivability, contributed to their high ratings. Additionally, 18 taxa received four-star good ratings for similarly strong performances.

Speedwells are generally easy to grow and prefer sunny locations in moist, well-drained soils. Plants grown in less light will not bloom as profusely and may become lax or open in habit. Crown loss or plant death may occur in wet soil conditions in winter.

Many speedwells require a midsummer shearing after the first bloom to promote a healthy new basal foliage and to encourage late summer flowering. Deadheading of spent blooms produces many new bloom spikes later in the summer. By selecting the best cultivar(s), you may avoid potential foliar diseases, including powdery mildew, downy mildew, leaf spots, and foliar rust.

Generally, plant disease pressure is more severe here in the Southern Appalachian Region than in the Midwest. Read the entire 8 page CBG report (Issue 33, 2010) authored by Richard G. Hawke.

Growing Spuria Iris Worth The Challenge

2010-03-15T13:30:00.000-07:00

photos courtesy of Iris City Gardens

Jimmy Turner, Dallas Arboretum horticultural guru, gave me this idea. Growing spuria iris in the Southern Appalachian region can be quite challenging. Hardy to USDA zone 5, spurias are dormant (asleep) during our usually hot, dry summers. A wet summer is a real “downer” for spurias.
Spuria irises bloom two weeks after the popular tall beard iris. They grow and flower best under full sun. Spurias are not choosy about soil type and pH. Bloom stalks can reach 4+ feet in height in a good garden soil.
Foliage dries up in the heat of summer, very natural for spuria iris. Gardeners should not attempt to revive them with irrigation. Autumn showers revive plants. Once growth re-starts, plants hate to dry out.
Spurias need one year to become established. Space plants at least 3 feet apart. Divide them every 5 years. Natural rainfall in our region is usually plentiful. The easiest way to kill spurias is to mulch and overwater them.
You may purchase spurias from several mail order nurseries or local nurseries which specialize in iris. Personal shopping emporiums include Iris City Gardens in Nashville, TN and Heritage Gardens in Greeneville, TN.

Time to Plant Early Vegetables

2010-03-14T07:46:00.000-07:00

Photo credited to University of Illinois Extension

Spring weather seems to have finally arrived here in the Southern Appalachian region. While the weather has changed for the better. Night time temps have remained above 30° F over the past 8-9 days. Spring frosts in the morning are common in this region into early May. More snow showers will likely occur, so it is wise not to stow away the snow shovel just yet.

St. Patrick's Day (March 17) signals the traditional start for planting early veggies, called the cole crops, within USDA zones 6-b to 7a. Night temps in the mid-20's are unlikely to injure these cool season vegetables.

Why the early start? Well-rooted young plants in March better cope with the warm 70°F days ahead in April and May. Poorly established vegetables like cabbage, broccoli and cauliflower get "heat stroke" on hot days and likely will bolt (go to seed).

Plant your greens - lettuce, mustard, spinach, chard and kale. Turnips provide both greens and edible roots. Root vegetables such as carrots, potatoes and radishes are part of the early spring agenda.

For carrots to develop well, they require a loose, friable soil. Most of us garden in a tight, clay soil. I advise planting carrots in a raised bed, mixing generous amounts of compost into your soil, creating a porous and deep-rooting grow medium.

Re-blooming Amaryllis -- Just Add Water

2010-03-10T14:48:00.000-08:00

An amaryllis bulb is nature’s equivalent of a re-chargeable battery. In the fall stop watering to push the bulb into dormancy (sleep). Most leaves wither and die within 4-6 weeks. Remove a dried leaves (for neatness). The bulb must remain dormant for a minimum of 8 weeks. Store the pot anywhere, in a closet shelf or out in the garage, provided the storage temperature does not drop below freezing (32° F).
Every few weeks, restart a potted amaryllis bulb. Place in an east or south-facing window of your home, and add water. Pre-mix a water-soluble fertilizer in the water according to manufacturer’s directions. First watering requires that you sink the pot bottom in a pail of water/fertilizer for 2-3 hours to fully adsorb water and nutrients. Turn the pot weekly so the plant and flower stalk grows straight up.
Your amaryllis will bloom in 4-6 weeks. Enjoy it! After flowering, continue to water and feed the plant until it can be moved outside onto a sunny deck or patio in mid to late spring after the frost danger has past. Your amaryllis will flourish through the summer months and will be fully recharge by autumn.
Repot your amaryllis every 3-4 years in the fall after dry-down. Divide and give away the extra bulbs to garden friends to enjoy. I enjoy shopping for new amaryllis bulbs at local garden shops and on-line at http://www.brentandbeckysbulbs.com/

“Pruning Cuts –Avoiding the Big Ones”

2010-03-08T12:50:00.000-08:00

Question: was this pruning cut a mistake? You judge.
Driving home yesterday, I spied upon this extreme pruning cut (see photo). The tree pruner may have read the chapter in the pruning manual about cutting a damaged or broken limb on an angle to shed snow and rain. Had he/she missed the chapter that recommends making the smallest possible cut? This cut is very large.

Whenever possible, make small cuts and on a 30°- 45° angle. I have the advantage of seeing the oak tree up close. In this case, tree pruner may have experienced extenuating circumstances. I had not seen the extent of injury to this storm damaged tree. I've concluded that this tree cut is correct.

Each pruning cut is a wound. A small cut heals more rapidly than a wide cut. Cutting on an angle is correct, creating the smallest possible diameter wound. There is no need to apply a tree wound paint or sealant. These products are simply cosmetic.

Prune most trees and shrubs in late winter unless they flower in spring. If you delay, spring-flowering plants may be pruned within one month after blooming. Prune summer-flowering shrubs and trees in late February and March because their flowers are initiated on new spring -summer growth.

Aucuba -- the "Holly" of the Shade Garden

2010-03-06T08:18:00.001-08:00

On a recent trip to the Knoxville Botanical Garden, I was re-introduced to a shrub, not used as much as it should be - gold dust plant (Aucuba japonica). Hardy to garden zones 6b-10, aucuba is at home in part sun to heavily shaded areas in the garden. Direct sunlight, even in the darker winter season, will scorch the foliage.
I've enjoyed a "plain green" foliage variety in my landscape over the past 16 years. It is tucked among three Japanese maples. Its holly-like leaves and bright red berries (on female cultivars)become more noticeable after the surrounding maples have surrender their fall plumage.

Many gold leaf cultivars sparkle in an otherwise dreary winter garden. Many cultivars abound. I particularly like 'Picturata', exhibiting large bright golden splotches in the center of each leaf and splashed by tinier yellow specks.

Branches on this 8-10 foot tall shrub are upright in habit. Growing culture is the same as hollies - preferring a well-drained, richly composted and moist soil site.

Japanese Apricot Blooms in Winter

2010-03-01T07:35:00.001-08:00

Japanese apricot (Prunus mume) is a beautiful reminder that the worst of winter may be behind us. On days barely above freezing, the light pink fragrant blossoms open, rarely in great numbers. Cold nights freeze the blossoms but other buds will open during the next warmup.

Japanese apricot is cold hardy in garden zones 5 thru 7. It is a small 10-12 foot tree, rarely bearing fruit. Plant in a full sun area of the garden, near decks and patios where you can visually enjoy the winter bloom from inside your warm home. The tree is likely to coax you outside.

Japanese apricot does not prosper in hot or dry locations. Plant in a moist, well-drained soil, mulch when needed, and prune to maintain an open branched tree. Over a dozen cultivars are available in white, pink, or red tones and single, semi-double or double blossoms.

'Cassata' -Not Your Typical Daffodil

2010-02-24T18:37:00.000-08:00

photo by Susan C. Morgan, Horticultural Manager at the Dallas Arboretum

I found this among my daughter Susan's Facebook photos: Narcissus 'Cassata'. Cassata is her favorite daffodil -bar none.

The creamy white flower of 'Cassata' is a unique bright yellow split corona (cup) which matures to white. The reflexed "petals" from the split cup are ruffled and lie almost flat against the rear white petals.

Cassata blooms early to mid- spring among other narcissus. Plant size is 16 to 18" tall.

Bulbs will naturalize in USDA Zones 4 to 8.

Cassata is for sale in the fall catalog of Brent and Becky's Bulbs, a mail-order bulb emporium in Gloucester, VA. Check them out on thewebsite: http://www.brentandbeckysbulbs.com/

'Bosque' Lacebark Elm - a Better Choice

2010-02-20T10:50:00.001-08:00

(New planting of Allee elm pictured)

Recent storm damage has caused a re-evaluation, whether to continue to plant the cultivar Allee®, also called ‘Emerald Vase’. Urban foresters around the state of Tennessee report that limb breakage and clean up around Allee elms is greater than around other cultivars. Bosque seemed to fare much better.

Lacebark elm (Ulmus parvifolia) is a beautiful medium -sized street and shade tree. Its use in urban street plantings has become popular over the past decade. The three leading cultivars of lacebark elm are Allee®, Athena® and Bosque™.

The tree earns its name from the delightful orange or brown color mosaic or puzzle-like pattern over the main trunk (s) and branches. The autumn leaf color is rarely memorable and the small 1-2 inch leaves fall without much fanfare and leaf litter mess.
Get your lacebark off to a long and prosperous life by supplying extra water and light fertilize feeding the first two years. In the first two years after planting, a young tree needs deep watering every two weeks in the late spring and summer. An established lacebark elm exhibits exceptional drought tolerance.
If you or your city, town or village is planting lacebark elm in your housing subdivision, request that they select Bosque elm.

Tips on Planting an Apple Orchard

2010-02-17T08:19:00.000-08:00

Apples are easy to grow with a little planning. Select the varieties based on what you like to munch on. Visit the local supermarket and buy several to sample. Some apples taste better in pies and in sauce. Some varieties have a short shelf life and must be consumed within a few weeks after picking or purchase. Favorites like 'Granny Smith' and 'Rome' are good for eating, baking pies and making sauce.
How long are you willing to wait? Apple trees grafted on seedling rootstocks begin bearing fruit in 7-8 years. Varieties grafted to dwarf (grow 9 feet tall) or semi-dwarf (12-15 feet tall) rootstocks begin bearing a crop within 3 years.

Young trees should be allowed to grow and never permitted to bear fruit. Space semi-dwarf trees 15-18 feet apart and dwarf trees at least 8-10 feet apart. Plant two or more different varieties for adequate cross pollination.
Plant trees either in late winter (before spring) or in the autumn in an open sunny site. Mulch trees to 2- 3" depth with a minimum 18 inches diameter around each tree trunk. In late fall pull mulch away and loosely wrap the tree trunk to a 2 foot height (add another foot if you live in heavy snow zone) with hardware wire (cloth) to prevent rabbits and pine voles (mice) from chewing on the tender sugary bark of a young fruit tree.
Finally, order trees early and request delivery before the first day of spring.
Check with your local Extension agent or agricultural university for additional information about growing apples.
Popular apple varieties:

Gala-yellow-orange to red /fresh/early
Empire -dark red over green background/ fresh, cooking/ early

Red Delicious -red/fresh/early midseason
Jonagold-yellow with light red stripes /fresh, cooking /midseason
Golden Delicious-yellow green to light yellow/fresh, cooking /midseason
Fuji -green with red stripes/fresh /late midseason
Stayman-blush to red /fresh, cooking/late
Rome-blush to red /fresh, cooking /late
Granny Smith -greenish-yellow/fresh,cooking/late

Native Viburnums

2010-02-16T14:58:00.000-08:00

photo -Arrowwood viburnum in late summer

A trip to Carolina Native Plants Nursery in Burnsville, NC gave me this idea to list those viburnums which are U.S. natives in plant zones 6-7. All are worthy for planting in your landscape in full sun except where noted. All attract birds and other wildlife to your property.

Mapleleaf vibrnum (V. acerifolium) - prefers dry shade sites
Witherod viburnum (V. cassinoides)
Arrowwood viburnum (V. dentatum) - hardy north into zone 3
Sheepberry, nannyberry (V. lentago) -hardy north to zone 3
Smooth witherod viburnum (V. nudum)- superior cultivar 'Winterthur'
Small viburnum (V. obovatum)
Black haw viburnum (V. prunifolium) -in part shade areas
Rusty blackhaw (V. rufidulum)
American cranberrybush (V. trilobum)- try cultivar 'Wentworth'; hardy to zone 2

Fragrant Wintersweet in Bloom Now

2010-02-15T08:30:00.000-08:00

It's mid-February and you may have already missed seeing the fragrant yellow blossoms of wintersweet (Chimonanthus praecox). Its tiny flowers, 3/4 to 1 inch across, open in the coldest period of the winter season. Blooms are weather-proof, rarely injured when nighttime temps dip below freezing in zones 6 and 7. Bloom injury likely occurs as evening temps approach zero °F.
Wintersweet is a 10-15 foot tall and wide shrub, and grows well in any soil type provided it is adequately drained. Summer foliage is lustrous dark green, turning yellow-green in fall before dropping its leaves.
Every 5 to 6 years, a tall, often leggy fragrant wintersweet requires a complete rejuvenation. Prune the entire shrub back to within 4-6 inches from the ground after blooms have vanished in late March. It will grow back rapidly and bloom again next January.

Thermotropism in Plants

2010-02-15T07:30:00.000-08:00

How cold is it outside this morning? Look out the window....perhaps your rhododendron is telling you.

On very cold winter mornings some broadleaf evergreen shrubs, like rhododendron and daphniphyllum in my landscape, droop down and/or curl up. (see photo). This is a specific response by some plants to sub-freezing temperatures, called “thermotropism”.
Scientists do not fully understand the cause of this foliar response. It may have something to do with leaf cell hydration. Thermotropism also may protect leaves during periods of high irradiance by sunlight. It may protect from cold temperature injury during daily thawing and re-freezing inside the leaf of some broadleaf evergreens.

On most days, leaves unfurl to their full natural position by late morning as temps rise above 32 °F (0 °C). Remember to water evergreen shrubs every 2-3 weeks if natural rainfall and snowfall are more than 60% below seasonal averages.

Privacy Screening - Avoid Using Leyland Cypress

2010-02-11T12:30:00.001-08:00

(Pictured-- Leyland cypress screen)
'Green Giant' arborvitae and Cryptomeria (Japanese cedar) have proven more dependable over the years than Leyland cypress across Tennessee, Virginia, North Carolina, and South Carolina. Leyland cypress is susceptible to three serious foliar diseases.
Some people love the faster growth of Leyland cypress. Leyland cypress may be weak-wooded, as reported by some gardeners this current frigid winter. Fast growing species tend to be weak-wooded. This may be the problem with the heavy snow and high wind storms this past winter.
Ask yourself "do you really need to construct a 50-60 foot green wall so you can hide from the sight and noise of your neighbors". A 10 to 12 foot screen is usually what most people need.
I would sway you to choosing a shorter and slower growing needle evergreen like Emerald™ arborvitae, any tall-growing evergreen holly (Ilex spp.) or an evergreen flowering shrub like Pragense viburnum.

New Dogwoods for Mildew Resistance

2010-02-11T10:58:00.001-08:00

'Joy' 'Mist' 'Snow' 'Blush'

Powdery mildew has become more of a problem across the southeastern U.S. over the past ten years on flowering dogwood (Cornus florida). University of Tennessee plant scientists have developed a series of mildew resistant dogwoods (pictured above). Each cultivar is sold under the Appalachian series of dogwoods. In cool spring climates, the white floral bracts of 'Appalachian Blush' will develop a pinkish blush. Generally, the color blush is rarely observed in Tennessee, Virginia, Georgia, North Carolina and South Carolina.

These cultivars join 'Cherokee Brave' (dark pink bracts) as the only powdery mildew resistant dogwoods. Only in a rare occasion will you need to spray these dogwood cultivars.

'Bosque' Lacebark Elm -- a Better Choice

2010-02-10T13:22:00.000-08:00

(New planting of Allee elm pictured)

Recent storm damage has caused a re-evaluation, whether to continue to plant the cultivar Allee®, also called ‘Emerald Vase’. Urban foresters around the state of Tennessee report that limb breakage and clean up around Allee elms is greater than around other cultivars. Bosque seemed to fare much better.
Lacebark elm (Ulmus parvifolia) is a beautiful medium -sized street and shade tree. Its use in urban street plantings has become popular over the past decade. The three leading cultivars of lacebark elm are Allee®, Athena® and Bosque™.
The tree earns its name from the delightful orange or brown color mosaic or puzzle-like pattern over the main trunk (s) and branches. The autumn leaf color is rarely memorable and the small 1-2 inch leaves fall without much fanfare and with little mess.

Get your lacebark off to a long and prosperous life by supplying extra water and light fertilize feeding the first two years. In the first two years after planting, a young tree needs deep watering every two weeks in the late spring and summer. An established lacebark elm exhibits exceptional drought tolerance.

If you or your city, town or village is planting lacebark elm in your housing subdivision, request that they select Bosque elm.

'Clothed in Glory' daylily

2010-02-10T09:53:00.000-08:00

(Photo courtesy of The Daylily Nursery)

Browsing through several garden catalogs on this snowy February day, I spotted a new daylily gem called 'Clothed in Glory' from The Daylily Nursery, a mail order emporium in Rock Island, TN.

Tim Hitchcock, nursery owner, describes 'Clothed in Glory' as an 18- inch tall lavender beauty possessing regal golden frilled-edged petals with a yellow center eye. Each flower measures 7 inches across and the floral bud count is enormous. 'Clothed in Glory' re-blooms in early fall if kept watered and fertilized over a hot, dry summer.

Daylilies are low maintenance perennials which grow in any well-drained soil. Very few disease and insect pests bother them. Plant them in early spring and daylilies will bloom their first summer (late spring). Divide daylilies every 5-6 years to maximize flower numbers.

With over 84,000 registered daylily daylilies in the world marketplace, gardeners still rally around the popular 18-22 inch tall landscape cultivars: 'Stella D'Oro', 'Pardon Me', and 'Happy Returns'. I recommend adding 'Clothed in Glory to your garden this spring.

Salt Damage on Trees

2010-02-01T10:54:00.000-08:00

Winter 2010 lingers on across Tennessee, Virginia and North Carolina. The white coating of de-icing salts over streets and highways can damage many trees and shrubs. Salt spray and salt deposits may also leach into the soil and become equally damaging. Plant species vary in their sensitivity to salt injury.
Browning of the tips of needle and broadleaf evergreens is a typical symptom of salt injury. Needle loss can be an extreme result, with evergreen branches becoming progressively bare. Often, evergreens become so weakened and stressed that new spring growth does not slow the needle/leaf loss. Overall tree health gradually declines.

The following practices can minimize salt injury to trees and shrubs:
1. Applications of water will leach some salt out of the root zone. Plentiful spring rainfall will help in this leaching/cleansing process. As much as 6 inches of water is needed to leach about half the soluble salts. In addition, applying gypsum (calcium sulfate) displaces the sodium in the soil.
2. Plant trees in salt-prone areas that are less vulnerable to salt damage. All trees are affected by salt to some degree, but some species are more tolerant than others. A listing of the susceptible and resistant trees to salt (University of Tennessee Extension publication SP-610) appears below.
3. In future plantings, avoid setting salt susceptible tree species in areas where salt-laden brine and slush are likely to accumulate.
4. Plants that are injured and exhibit dieback should be watered, pruned and fertilized.
Fresh mulch may be applied to help reduce water loss during the normally dry summer ahead. Weakened or stressed trees are also more susceptible to disease and insect pests.

Table 1. Salt Susceptibility of Trees
Vulnerable to Salt
Red Maple - Acer rubrum
Sugar Maple - Acer saccharum
Mimosa - Albizia julibrissin
Serviceberry - Amelanchier spp.
American Hornbeam - Carpinus caroliniana
Dogwood - Cornus florida
Hawthorn - Crataegus spp.
American Beech - Fagus grandifolia
Yellow Poplar - Liriodendron tulipifera
Crapemyrtle - Lagerstroemia spp.
Magnolia - Magnolia grandiflora
Spruces (most) - Picea spp.
Eastern White Pine - Pinus strobus
Scotch pine - Pinus sylvestris
Lindens - Tilia spp.
Eastern Hemlock - Tsuga canadensis

More Tolerant to Salt
Norway Maple - Acer platanoides
Buckeyes - Aesculus spp.
Birch - Betula spp.
Hickories - Carya spp.
Ash - Fraxinus spp.
Ginkgo- Ginkgo biloba
Honeylocust - Gleditsia triacanthos
Black Walnut - Juglans nigra
Eastern Redcedar - Juniperus virginiana
Cottonwood/Aspens - Populus spp.
Cherries - Prunus spp.
Oaks (most) - Quercus spp.
Black Locust - Robinia pseudoacacia
Yews - Taxus spp.
Elms - Ulmus spp.

Ferns in Your Garden

2010-01-22T06:44:00.000-08:00

I recommend adding ferns in your shade garden. Ferns offer very fine textured foliage. Plant'em in clumps of three or more. Select the proper fern by your garden site, e.g whether it is likely dry or moist soils. Some grow surprisingly well in full sun, but most prefer partial to full shade. Don't buy a collection of different ferns for planting in one garden place. Instead, select them by their light and soil moisture needs.

Here are four species which are easy to grow:

Christmas fern (Polystichum acrostichoides)
Autumn fern (Dryopteris erythrosora)
Lady fern (Athryium felix-femina)

All four are not finicky, demonstrate good drought tolerance and grow in soil with little to no additional soil prep. Ideally, you should them in a richly composted garden soil along with adequate moisture over long dry spells. A weak fertilizer solution monthly from April to August will get all off to a good start in the first year.

Northern maidenhair fern (Adiantum pedatum) - (pictured)- prefers well-drained, highly composted soils and supplemental moisture during long summer dry spells. Keep soil near pH 7.0 (neutral) by occcasional liming every few years if soil pH drops.

Better Winter Blooming Witchhazels on the Way

2010-01-16T08:49:00.000-08:00

Chinese witchhazel (Hamamelis mollis) are a mid-winter garden delight. Depending on the cultivar, small yellow, orange or red flowers open in early February. Flowers survive many cold nights unharmed over several weeks.

Most of the Hamamelis x intermedia hybrid types hold onto their leaves during the winter in the southeast. The popular cultivar 'Arnold Promise' is one of the worst offenders for winter leaf retention.

Chinese witchazels retain (don't drop) their dried leaves through most of the winter, essentially hiding most of the tiny flowers beneath them. Autumn weather plays an important factor. If fall temperature drops are gradual, leaves will drop. A warm fall followed by a quick cold snap will stick leaves to branches all winter long. Often, this is what occurs in the southeastern U.S. (garden hardiness zones 6b - 8a).

1-15-10 Conversation with Brian Upchurch at Highland Creek Nursery in Fletcher, NC
Brian recommends planting Chinese witchhazel cultivars which tend to shed all foliage before flowering starts. His favorites are 'Wisley Supreme' (bright yellow blooms), 'Robert' (orange) and 'Twilight' (red). He adds that all three do not suffer from powdery mildew foliar disease as Arnold Promise does over the summer months. He adds that the cultivar 'Westerstead' is a better choice than Arnold Promise in the hybrid witchhazels.

Winter Flowering Bulbs

2010-01-07T13:33:00.000-08:00

Photo: Galanthus naturalized in woodlands (courtesy of Brent and Becky's Bulbs)

These bulbs are the early birds. Give them a week of warm weather in the 50's, nights slightly above freezing, and little to no snow cover. A beautiful flowering patch of winter aconite (Eranthis), snowdrops (Galanthus), glory of the snow (Chionodoxa), or early crocus appears in January and February in USDA zone 6 and 7.

These "special" bulbs naturalize and come back every year. Bulbs are planted in the fall and are purchased from bulb emporiums on-line or through mail order nursery catalogues. Two personal favorites for purchasing bulbs are Brent and Becky's Bulbs in Gloucester, VA and van Bourgondien's Bulbs in Dix Hills, NY.

Dec. 21, 2009 conversation with Brent Heath: he identified additional early flowering gems in the winter garden in zone 6: The earliest daffodil is Narcissus 'Rijnveld's Early Sensation' with golden yellow opening in mid-to late January in zone 7. Flowers last and last in the cold winter weather. Many species crocus bloom in February and March. Crocus ancyrensis 'Golden Bunch' opens with small tangerine yellow blossoms, one of the earliest to bloom in the winter season. Other early bird crocus species are C. imperati and C. tommasinianus.

Muscari armeniacum 'Christmas Pearl' bears 4-6 inch double blue flowers beginning in late February.

Disease-free Apple Varieties--Judge for Yourself

2010-01-06T17:33:00.001-08:00

Weekly spraying of home apple orchards for the dreaded apple scab is a total downer. Over the past half century have come the first scab-free immune apple varieties: Prima, Priscilla, and Sir Prize. However, Prima and Priscilla will never win any taste awards.

All 3 varieties are very susceptible to other apple disease maladies as cedar-apple rust, powdery mildew and fire blight. All are rated as dessert quality, possessing a short shelf life after picking.

Currently, the Penn State Extension website lists Freedom, Enterprise, Liberty, Novomac, Pristine, Redfree and Sundance with good resistance to 3 of the 4 major diseases.

Select 2 -3 varieties as apple trees require cross-pollination. Purchase them on a dwarf or semi-dwarf rootstock, properly prune them annually, and you'll be harvesting fruit from trees in 3 years.

Pruning An Old Nandina

2010-01-05T11:15:00.000-08:00

Nandina (Nandina domestica) is often mis-pruned. By shearing or topping nandina foliage, blooms and resulting berries are lost (see photo). The plant eventually becomes leggy and thin.

Sharply prune back about a third of the taller stems at the base of the shrub in March before spring growth begins. Stagger the cuts 3 to 6 inches above the soil. Within a few months new shoots begin to grow out near the soil line, eventually filling in around the shrub base. The regrowth gives the nandina a fresh appearance.

Why My Tree Or Shrub Doesn't Bloom

2010-01-05T07:08:00.000-08:00

Frustrated by a fruit tree or ornamental tree that does not bloom? There are 5 primary causes:

Lack of sunlight - insufficient light reduces flower bud development
Fertility - too much nitrogen fed to plants can over-stimulate vegetative growth, either delaying or preventing flower bud development
Winter injury or chilling tender flower buds in one or more spring frost
Pruning at the wrong time of year, essentially removing all flowering wood
Alternative (biennial) flowering when a plant bears too much fruit and will not initiate new flower bud for the next year

All these factors are inter-related. While bad pruning practices may reduce flower bud numbers, good timely pruning practices increase blooming. Usually, an unpruned tree or shrub does not bloom heavily. A shrub or tree with an open branch canopy in full sun will flower reliably every year.

Prune spring flowering shrubs and trees immediately after flowering. These plants set flower buds on woody growth produced in the summer. Summer-flowering plants set their flower buds on spring wood in the same year when they bloom. They can be pruned in late summer or wait until late winter and early spring.

Big Begonias

2010-01-04T14:29:00.000-08:00

The Benary 'Big Begonia' series are a hit, "begonias on steroids", some gardeners may say. Individual flowers are twice that of other bedding begonias. Colors are vivid with three cultivars currently available . 'Big Rose Bronze Leaf' is my personal favorite. (pictured)

Begonias grow best in well drained, humus-rich garden soil. Provide tender -loving care for the first 4 weeks in the spring, and plants will bloom non-stop through a long hot, dry summers into the first hard frost autumn.

Plant the Big begonias in full sun or partial sun (a minimum of 5 hours of sun recommended). Disease and insect pests are rarely an issue for these tough, non-stop flowering annuals. Do not plant begonias in the same garden spot more than 3 consecutive years to avoid buildup of soil pathogens.

Angelonia in the Summer Garden

2010-01-04T11:48:00.000-08:00

Tired of marigolds and petunias? Angelonias (A. angustifolia) are superior summer garden annuals. Angelonias require very little care. They possess superior heat and drought tolerance.

I prefer the Serena series (seed produced type) because local greenhouse growers produce and sell them more cheaply. Vegetative (cutting) type angelonias grow taller, are heavy bloomers, and are more pricey at garden centers.

Varieties of 'Serena' angelonia come in white, pink lavender, lavender, and purple flowers. Plant them after the danger of spring frosts in your gardening area is low. After planting, follow-up with a few early waterings. Then, sit back and enjoy angelonas in constant bloom from late spring to the first hard frost of autumn.

Serena angelonias grow 12-15 inches in height and 14-16 inches in spread in my zone 6-b garden.

photo: pentas (front) and 'Lavender Pink Serena' angelonia (rear)

Root Injury to Container Plants

2010-01-02T10:13:00.000-08:00

The 4 most common reasons why gardeners lose outdoor container plants during the winters are:
1. Sub-freezing temps
2. Soil freezing for long periods
3. Waterlogged roots
4. Dessication from dry winter winds

Roots are not as cold hardy as above-ground shoots, trunks, branches, etc. Evergreen plants become more challenged when the soil media is frozen. Their leaves demand more water and nutrients that the roots are not able to supply from the frozen ground.

Root injury for most woody tree species begins at 22°F. This is soil that has little water in it. Keep in mind that water freezes at 32°F. So, one tip is to keep container plants watered, but not waterlogged. Most plants are injured when soil temps hit 16°F over a 24-hour period.

Pots must provide adequate drainage. Planting in a soil-less media containing high percentages of an organic component such as peat moss and/or compost, plus a gritty substance as coarse sand, tiny pea gravel or perlite for aeration and drainage. The pot should include bottom holes to weep out excess moisture.

Evergreens naturally shed most rain and snow like an umbrella and supplemental watering is critical for these plant compared to deciduous plants. Irrigate containers at least twice monthly, assuming that natural rain and snowfall will supply the rest.

Coral Bark Maple Blazes in the Winter Landscape

2010-01-01T16:22:00.000-08:00

Sango kaku Japanese maple (Acer palmatum 'Sango kaku') has light green summer foliage on a fairly upright branches. In the fall, foliage turns yellow-gold with some light tints of red, otherwise a very ordinary tree. It's in the fall and winter seasons when this 20-25 foot ornate maple excels. The green branches and twigs turn bright coral red, aglow in the winter sun. Sango kaku makes a beautiful addition to any landscape in USDA zones 6-7.

Sango kaku prefers 1/2 day of sun, preferably in the morning and early afternoon hours. New spring growth is thin and rank, the tree needing pruning annually to maintain a good tree form. A colder than normal winter often results in twig dieback, requiring minor cleanup pruning cuts in the spring.

'Beni kawa' is another Japanese maple with exquisite salmon colored bark beginning in late fall-winter. It appears to possess better cold and heat tolerance. Tree height is alot smaller, perhaps only 10-12 feet tall at maturity. Growth on Beni kawa is not as spindly and less prone to winter twig dieback. Beni kawa leafs out 2 weeks later than Sango kaku, avoiding spring freeze injury.

Princess Lilies -- Perennial in Zone 6

2009-12-29T08:50:00.000-08:00

Not all alstroemerias are alike. I have been enjoying my Princess lilies (alstroemeria hybrids from Holland) over the past 6 years. They have been surprisingly winter hardy in zone 6-b where I garden. Further south in zones 7 and 8, Princess lilies prefer part sun to partial shade.

I grow'em on the east side of the garden in full sun. The harsh afternoon sun of summer is filtered through the tall shrubs and trees nearby. Mulching the soil provides extra freeze protection to roots in the winter and guarantees their return next spring.

Princess lilies need little care after planting. I feed'em a handful of granular 10-10-10 around each plant in late winter. Give them a weekly irrigation for 1/2 hour or more during summer dry spells. Plants grow short and compact and are also suitable for containers on the deck or patio.

Currently, there are 17 varieties, richly colored in whites, yellows, pinks and reds. This spring I will be adding 1 or 2 new Princess lilies to the perennial flower border .