Tuesday, July 3, 2018

Lovely Panicle Hydrangeas

Limelight hydrangea at NC Arboretum in Asheville

Beautiful panicle hydrangeas (Hydrangea paniculata) are among the best hydrangea choices for the summer garden (USDA hardiness zones 3 to 8). They are perfect for use in containers or in groupings or masses, shrub borders, hedges, and screens.

Limelight® hydrangea has become the standard-bearer of panicled hydrangeas with huge 6 - 8 (12) inches chartreuse (off white) flower heads in mid-summer. Limelight is a more compact selection 6 to 8 feet tall and wide over time.

Fall leaf color is usually blah in shades of yellow in fall. Flowers of some cultivars age gracefully with floral heads turning lightly pink. Panicled hydrangeas are suitable as fresh cut or dried flowers.  

Plants grow from 3 - 10 feet high depending on the variety chosen. For best flowering grow shrubs in full sun to light shade and in moist, but well-drained soil. Shrubs bloom on new wood in summer, and are pruned to desired size and shape in early spring.

For smaller landscapes, there are several smaller panicle hydrangeas to choose.

Bobo® hydrangea - fluffy, creamy spikes that turn to deep pink with red highlights on bold, red stems. Earlier blooming Bobo opens 1-2 weeks before other H. paniculata varieties start blooming. Bobo grow 3–5 feet tall, and is an ideal choice for small gardens and growing in large containers.

Little Lime® hydrangea – a dwarf version of Limelight® grows 5-6 feet tall and wide, and boasts chartreuse florets that turn creamy and then mature to rosy pink. Often all three colors coincide. Little Quick Fire panicle hydrangea, 4 to 5 feet tall and 3 feet wide, blooms early in the season with white panicles that mature to rosy red.

Little Quick Fire® - the smaller version of H. paniculata Quick Fire® @ 3-5 feet tall and to 2-4 feet wide. It blooms early (almost 4 weeks earlier than other panicle hydrangeas) in upright panicles. Each panicle (to 6” tall) contains abundant showy sterile florets which emerge white but change to pink and finally reddish-purple as the summer progresses.

Little Lamb® - downsized version of H. paniculata ‘Grandiflora’ @ 6-8 feet tall and wide. Dense, cone-shaped panicles of mostly sterile, small white flowers. Panicles stand on upright to outward-arching, stiff sturdy stems. The much smaller, fluffy, fertile flowers are partially visible beneath the showier, sterile ones.

Pinky Winky Hydrangea - unique, large bi-colored, white and pink flowers that look nice against the dark green foliage of the plant. Its unique red stems rigidly supports large 12-16 inch blooms upright on the plant. The older flowers mature to dark pink while new flowers continue to emerge white. Pinky Winky hydrangeas grow 5-6 feet tall and 6-8 feet wide.

Friday, June 15, 2018

A Grand Tree Aristocrat - Southern Magnolia

Southern magnolia (Magnolia grandiflora) is native to the Southern U.S. (USDA hardiness zone 6-9). The species grows upward of 60 - 80 feet tall with a pyramidal habit when young and developing a rounded canopy at maturity. These evergreen magnolias are cherished for their attractive glossy dark green foliage and showy fragrant flowers. Large 5 to 6 inch pure white goblet shaped flowers appear sporadically from mid-spring thru late-summer. Ornate cone-like seed pods form after flowers have shed their creamy white tepals (petals). 

Young trees may not bloom for 3-5 years after planting. Its shallow roots may eventually lift sidewalk pavement as the tree ages. Southern magnolias grow 30 to 50 feet high, and some varieties need lots of room. This tree is happily suited to large commercial and residential properties, golf courses and public parks.

Four large cultivars are ideally suited for planting on wide boulevards, medians, parkways, urban parks, industrial sites and golf courses. Undersides of leaves are either green or rusty brown as noted.

  • ‘Bracken’s Brown Beauty’ (50 feet x 25 feet) - rusty brown back leaf
  • ‘Edith Bogue’ (40- 50 feet x 25 feet) – green back
  • ‘Claudia Wannamaker’ (50 feet x 30 feet) – green back
  • ‘DD Blanchard’ (50 feet x 30 feet) – brown back

Smaller growing cultivars are also available at garden centers:
  • ‘Little Gem’ and ‘Hasse  (35-40 feet in height)
  • Teddy Bear® and ‘Kay Parris’ (25-30 feet in height)

Little Gem grows very shrub-like and may encompass 20 or more feet of ground area. Hasse exhibits a tree-like habit and branching is primarily upright. Teddy Bear and Kay Parris grow slowly and are better choices for small landscapes.

Leaves and flowers are proportionally smaller that the species. The glossy foliage is thick and leathery, and dark green over both the upper and lower surfaces. Kay Parris foliage is reddish brown on the underside.

Trees shed older leaves in spring as new ones emerge. Occasionally, its evergreen boughs are weighted down and snap off under heavy snow and ice loads.

Friday, June 1, 2018

The Bigleaf Magnolias For Tropical Accent

Bigleaf magnolia at Biltmore Estates
Bigleaf magnolias represent four species: (Magnolia macrophylla), umbrella magnolia (M. tripetala), Fraser magnolia (M. fraseri), and Ashe magnolia (M. ashei). All are medium-size trees with huge leaves and large flowers that appear after the leaves unfurl. Bigleaf magnolia is native to the southeastern United States as far north to Ohio (USDA hardiness zones 5-8). A mature tree attains heights of 30 to 40 feet and develops an irregular pyramidal form. In the northern areas the tree is deciduous and semi-evergreen in the southeastern U.S.

A tree may take 10 or more years before first blooms develop. Goblet-shaped flowers are creamy white, are rose-purple at the petal base, and over 12 inches across. They open in early summer, mostly high inside the tree and mostly hidden within the dense foliage. Up close, flowers are pleasantly fragrant. Fruit is round to cone-shaped, rose-colored, and nearly 3 inches long; they're unique, persistent, and attract numerous bird species. When cones open, each red coated seed is held by a thin silk-like thread.

Leaves are alternate, simple, 12 to 36 inches long, and 7 to 12 inches wide. They’re bright green on the upper surface and silvery gray beneath. Petioles are 2 to 4 inches long. Their yellow fall color rarely stands out. Leaves are intolerant of most urban pollutants.

Their enormous size foliage make them true horticultural oddities. Fall foliage drops, creates lots of leaf litter and decomposes slowly. The leaf debris may cover over or smother some types of ground covers. Weak branches and huge leaves should be sheltered from wind and ice storms.

Tuesday, May 15, 2018

Four Easy To Grow Ferns

Northern  maidenhair fern
Ferns add a delicate touch to your shade garden. Their foliage is very fine textured. Group three or more ferns 2-3 feet apart. Select the specific fern for the 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. Select ferns according to their light and soil moisture requirements.

Here are four species which are easy to grow:
  • Christmas fern (Polystichum acrostichoides)
  • Autumn fern (Dryopteris erythrosora)
    Autumn fern
  • Lady fern (Athryium felix-femina)
  • Northern maidenhair fern (Adiantum pedatum) - (pictured)
All four ferns prefer a well-drained, highly composted soil and supplemental moisture during long summer dry spells. Keep soil near pH 7.0 (neutral) by occasional liming every few years if soil pH drops.

All four are not finicky, demonstrate good drought tolerance and grow in soil with little to no additional soil prep. Ideally, you should grow ferns in a richly composted garden soil along with adequate moisture over long dry spells. Bi-monthly feeding with a water soluble fertilizer such as Miracle-Gro™, Jack’s™, or Nature’s Source™ from April thru August will get all off to a good start in the first year.

Tuesday, May 1, 2018

Keep Your Eye on Red Buckeye

Spring blooming Red buckeye
Red buckeye (Aesculus pavia) is a large shrub or low branched tree maturing to a 15 - 20 feet in height and spread. This southeastern U. S. native is becoming more recognized as a good selection in small urban landscapes.

The red buckeye tree flowers young, either in full or partial sun. Numerous 5- to 9- inch long floral heads sit at the ends of branches like decorative candles in late April and May. Flowers open just before the leaves begin to emerge. Flower color on individual trees varies from dark pink to scarlet red. A yellow flowering form is known to exist. Hummingbirds arrive to pollinate the individual funnel-shaped blossoms.

Lovely dark green, palmate compound leaves clothe the branches in the spring and early summer months. The polished dark buckeye seeds fall from the tree beginning in late September, quickly grabbed up by squirrels and others. Seeds are poisonous.

Disease and insect problems are of little consequence in the spring and early summer months. Disease blotched foliage that may also be scorched on the edges, the result of dry summers, results in a premature leaf drop by late August and September. Expect little to no autumn foliage color as branches are typically bare.

Sunday, April 15, 2018

Growing Blueberries In Your Garden

Both highbush and rabbiteye blueberries (Vaccinium spp.) are hardy in most regions of the U.S. Hot humid summers are problematic for highbush varieties and extremely cold winters can be injurious for rabbiteye blueberries.

Blueberry bushes grow 8-15-feet tall, requiring annual pruning. The soil pH should be in the range of 4.2 to 5.5. Their dark green summer leaves turn scarlet red in the fall. Pale pink flowers appear in the spring followed by the berries which start out as pale-green and ripen to dark bluish-purple.

Blueberries are very shallow rooted and must be irrigated regularly over the growing season. Space blueberry bushes 5 to 7 feet apart with rows 8 feet apart. As a base mulch use fabric matt and cover it with an additional 3 to 4 inches of sawdust, wood chips or pine needles. 

Feed each bush annually with a slow release organic-based sulfur-coated fertilizer. A newly blueberry plant starts out 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 5-6 years and should yield annually for 20-30 years.

For northern gardens (USDA hardiness zones 3-7), highbush blueberries ('Duke', 'Bluecrop', 'Bluejay', 'Jersey', 'Blueray' are favorite cultivars) are harvested.
In Southern gardens, rabbiteye blueberries (zones 7-9) yield best. Varieties include: ('Tifblue', 'Premier', 'Climax', 'Powderblue', 'Brightwell',  'Montgomery'). Consult the local Extension office for recommended blueberry varieties for your area.

Acclimated to southern climates (zones 6b-9), rabbiteye blueberries bloom in early spring and may be injured by late spring frosts. Varieties with a high chilling requirement may yield poorly in deep Southern areas.  Both kinds of blueberries require cross-pollination; a few varieties are  self-fruitful.
Birds love ripe blueberries as much as people do. Cover your bushes with netting to protect against birds during harvest time. Blueberries should be pruned annually.

Saturday, April 7, 2018

Multi-Purpose 'Evergold' Sedge

'Evergold' sedge
Japanese sedges (Carex oshimensis)  are fine-textured variegated sedges that typically grow as low, grass-like mounds or clumps. They are found in woodlands and rocky slopes throughout Honshu Island, Japan (USDA hardiness zones 6-8).

Japanese sedges are long-living and foliage is evergreen through most of their growing range. Narrow grass-like variegated leaf blades are upwards of 16 inches long by 5/16 inch wide. Brownish flower spikes appear on triangular stems in spring and have zero ornamental value. 

There are many fine cultivars. I recommend starting with an outstanding cultivar named 'Evergold'. It grows 12 - 18 inches high and 12-18 inches in spread in full shade to partial sunlight and in moist to average soil well- drained soil. Water well after planting and regularly until established after one year. Foliage color is richer in part shade. Plants spread slowly by short rhizomes and can be propagate by rhizome division in early spring.

Space plants 10 inches apart. Group or mass as a ground cover for edging along paths or sidewalks. Utilize as a specimen accent plant in a woodland or a rock garden. Evergold sedge can be planted in low spots and along the edges of a stream, pond, or a water garden. Evergold sedges make perfect additions to mixed containers and window boxes. The leafy mounds spill over the edge of containers

Trim back all last year’s growth around the start of spring. No serious insect or disease problems trouble sedges and are deer resistant.