Growing Lamb's Ears

Lamb's ears (Stachys byzantina)

Many gardeners are acquainted with the wooly leaf perennial called lamb's ears (Stachys byzantina). It is native to Europe and Asia (USDA hardiness zones 4-8). Summer heat and humidity takes its toll on lamb's ears, particularly in Southern climes.

Lamb’s ear (S. byzantina) forms a dense mat of woolly silver-gray leaves. Plants grow 12 -15 inches high by 18 inches wide. Spikes of purplish pink flowers appear on tall stems in early summer that detract from the foliage and, in my opinion, should be pruned off. Bloom stalks tend to re-develop and necessitate more pruning.

The cultivar ‘Countess Helene von Stein’, aka ‘Big Ears’ is the preferred choice as it exhibits showier velvety foliage, is more heat and humidity tolerant, and best of all, it rarely flowers (sorry bees!). Over time, it forms wider mounds and seedlings (from blooming species) will spread to other areas. The species develops a messy appearance and asks for pruning after flowers have quit.

Both types of Stachys are easily grown in moist well-drained soils and full to part day sun (6 hours or more recommended). Soils should be kept evenly moist, but established plants exhibit moderate drought tolerance. Plants spread by underground stolons. Set multiple plants 12-18 inches apart as a ground cover.

No serious disease or insect pests trouble lamb's ears. Pollinators can't resist the striking midsummer colorful floral spikes. Deer and rabbits generally stay away. Snails and slugs may be troublesome in wet summers.

Uniquely Different Franklinia Tree

Franklinia at NC Arboretum in Asheville, NC

Franklinia (Franklinia altamaha) is a U.S. native large shrub or small tree to 10-25 feet tall. Rated hardy in USDA hardiness zones 5-8, the tree seems best suited in zones 6 to 7.

Success with growing franklinia depends on purchasing a quality nursery plant, proper siting, and care, particularly during the first 2-3 years. Franklinia is only available from e-commerce nurseries and is best planted from late winter to early summer.

The species was first discovered growing in 1765 growing along the banks of the Altamaha River in southeastern Georgia by botanists John and William Bartram. The tree has been extinct in the wild since 1803. All franklinia trees are descendants from seedling propagated by the Bartrams in their Philadelphia, PA garden. Franklinia belongs to the tea family (Theaceae) and is closely related to Camellia, Stewartia and Gordonia (loblolly bay). The tree was named to honor Benjamin Franklin.

The tree’s most striking feature is its showy 2 – 3 inch pure white flowers with clusters of golden yellow stamens in the centers. Franklinia’s camellia-like flowers appear from late summer until frost. The blooms are sweetly-fragrant upclose.  Narrow, oblong-obovate, glossy dark green 3-5 inch long leaves turn several shades of orange, red and purple thru the autumn season. Branching is upright and spreading to create an open airy appearance. Ridged grey bark with prominent vertical white striations adds slight winter interest.

Franklinia grows best grown in humus rich, medium moisture, moderately acidic (pH 5.0 - 6.2) and well-drained soils and in full sun (in North) to partial shade (in Southeast). Franklinia prefers sites similar to azaleas and rhododendrons.

Fertilize in early spring with an acidic based soluble fertilizer such as Miracle Gro®, Miracid®, or Hollytone®. Franklinia also favors an annual feeding of Epsom salts (magnesium sulfate) @ 1 Tablespoon per gallon of water per tree.

Franklinia is valued as a specimen or a collector’s tree. Wilt and soil root rot (Phythoptera) are the serious problems. Proper siting of this unique tree is absolutely crucial. It is notoriously finicky to transplant because of its sparse fibrous root system.

July/August Blooming Plumleaf Azaleas

July/August Blooming Plumleaf Azalea

Plumleaf azalea (Rhododendron prunifolium) is a deciduous azalea that is native to  Georgia and Alabama mountains (USDA hardiness zones 6-9). It is one of the signature plants of Callaway Gardens in Pine Mountain, Georgia.

Their bright orange-red flowers surprise in late July into early Augusta and may last for 2 weeks or more. Compared to many other spring blooming native azaleas, flowers are not fragrant. Spring and summer foliage is medium-green and is mostly blemish-free.

Fall leaf color is also uneventful. Insect and disease problems are rare if the plant is properly sited. 

This 5-8 feet tall and wide shrub performs best in morning sunlight and shaded from the harsh afternoon summer sun. It thrives in well-drained, compost amended soil. Plumleaf azalea prospers in the calcareous clay soils found in the Appalachian region without pH correction.  Plant in full-day light shade in zones 7-9. Set the shrub into a shallow wide dug hole that has been generously amended with compost and/or peat.

Feed in early spring with a slow-release fertilizer such as Osmocote™ or Nutricote™. An alternative nutrition program is to use a water soluble product such as Miracle-Gro™ or Jack's™  in early spring and again in early summer. Maintain 2-3 inches of a pine-based mulch around the base of the shrub. Irrigate plant(s) the first 2 years of establishment.

Plumleaf azalea blooms on new current season's wood. Prune deciduous azaleas anytime after bloom to maintain a desired height and spread. Plumleaf azalea is primarily available at local native plant nurseries or is offered online.

Plumleaf azaleas are usually available from mail order companies on-line.

Hardier And More Colorful Hydrangeas

Summer Crush™ hydrangea

For over a quarter of a century, hydrangea breeders (Bailey's, Spring Meadows, and other nurseries) have introduced hardier, tougher, and more colorful bigleaf hydrangeas (Hydrangea macrophylla) that bloom on both new and old wood (USDA hardiness zones 5-8). 

Old wood flowers are set on last year’s growth and new wood flowers develop on current season's growth. It is important not to prune these hydrangeas late in the summer, as flower buds have already formed for the following spring.

Forver a quarter century, Proven Winners Colorchoice™ and Bailey’s Nurseries (Endless Summer™, Bloomstruck™, and Summer Crush™ brands) have introduced the newest hydrangea genetics. The Let's Dance™  series is worth a try in smaller gardens. A second option is to grow a different type of hydrangea Hydrangea serrata, or mountain hydrangea. New in this category from PW Colorchoice is the Tuff Stuff® series which have demonstrated superior bud hardiness and rebloom. Tuff Stuff Ah-Ha® reblooms heavily and has large doubled sepals on lacecap blooms, either pink or blue depending on soil (media) pH._­­­­­

American Yellowwood

May-June flowering tree

American yellowwood (Cladrastis kentukea), a member of the pea family (Fabaceae), is native to southeastern U.S. All other Cladrastis species are indigenous to Asia. Yellowwood is a beautiful medium-sized (35-45 feet) high tree with a broad crown, narrow profile, and upright branching.

Their pinnate compound leaves are alternately arranged. Each compound leaf is comprised 7-11 leaflets borne on a slender, green, 7-9 inches (20-30-cm) long rachis.

Dainty drooping panicles, almost wisteria-like, drip from the tips of branches in May or June, depending on regional location. The fragrant white-and-yellow pea-flowers are seldom borne on young trees and may take upwards of 10 years to bloom the first time. 

Yellowwood tends to be alternate-year bearing (i.e., bloom heavily one year, with little or no flowering the following year). Clusters of flattened green pea pods soon followed; each pod is 2-3 inch (10 cm) long and turns papery brown in autumn. Fall leaf color is brilliant yellow. The tree's light gray smooth bark, similar in appearance to beech (Fagus spp.), is an attractive four- season asset.

Yellowwood prefers a rich, deep, well-drained soil along with modest summer moisture. Leaves are subject to chlorosis (yellowing) in alkaline soils (pH above 7.2). This tap-rooted tree is drought tolerant within 2 years after planting. Yellowwood is not a good choice as a street tree as its surface roots may eventually push up sidewalks.

Narrow branch angles may result in limb trunked. When young, yellowwood needs to be correctively pruned to encourage wider branch angles and prevent bark inclusions. The cut branches tend to “bleed” sap excessively if pruned in winter.

Pests and diseases on yellowwood are rare, but the tree is susceptible to verticillium wilt. This thin bark tree is unfortunately subject to improper damage by line trimmers, mowers and other equipment, as well as sunscald over winter if young branches are left unshaded.

Venus® Is A Unique Flowering Dogwood

7" Bracts of Venus® dogwood (C. kousa x C. nuttali)

Spring flowering dogwoods (Cornus spp.) are back in vogue again (USDA hardiness zones 6-9). A better understanding about growing dogwoods coupled with improved resistant disease varieties have seen the return of dogwoods to landscapes again.

If you want to plant a variety with the largest flowers, no question it is Venus®. This hybrid dogwood (Cornus kousa 'Chinensis' x Cornus nuttalii 'Goldspot' x Cornus kousa 'Rosea')  was developed at Rutgers University by Dr. Elwin R. Orton (now retired). The tree's large bracted blooms measure 6 - 7 inches across in April and May. 

Venus dogwood grows vigorously, 15-20 feet tall (slightly greater in spread). It is a small deciduous tree forms a dense, low-branched, spreading habit.

Venus is resistant to anthracnose and powdery mildew diseases. It has clean dark green foliage and large flowers. Red dogwood fruits attract lots of birds in early fall. Fall leaf color is red to orange.

This dogwood grows in average, medium moisture, well-drained soils in full sun to partial shade. In southeastern U.S., morning sunlight and afternoon shade is best. Summer leaf scorch may indicate too much direct sunlight and/or exposure to hot, windy or dry soil conditions. The tree benefits by applying 2-3 inches of a wood-based or needle mulch that keeps tree roots cool and moist. For the first 2-3 summers, a young dogwood should be irrigated during dry periods.

Venus dogwood, when properly sited and cared for, have few disease and insect problems. Stressed trees become vulnerable to stem cankers and insect borers. Deer are usually not troublesome.

Dogwoods are planted on urban and suburban lawns and around patio areas. Venus dogwood needs to be special ordered from garden centers or purchase from e-commerce nursery sources.

Baptisias

'Purple Smoke' baptisia

Baptisia (Baptisia spp.) are beautiful long-lived low maintenance native perennials. Plants thrive in rich well-drained soil under plenty of sunlight. When planting, treat the roots as fragile and permit baptisia one year to establish itself. They will reward you with many years of spring flowering.

False blue indigo (Baptisia australis) was selected Perennial Plant Of The Year in 2010 by the Perennial Plant Association.  Most modern day cultivars are usually hybrids. Lovely spikes of purple (B. australis), lavender blue (B. minor), white (B. alba), bright yellow (B. sphaerocarpa) and bicolors appear in May (in Tennessee). Each species or cultivar blooms for 2-3 weeks.  Bloom stalks can be included in fresh flower arrangements

Plants grown in partial shade may appear stretched or leggy, requiring some staking. Fewer flower spikes are produced in shady places. I opt to remove the pea -like pods that form within a month after flowering because the weighty pods may detract from its shrub-like appearance. Plants are cut down to the ground in late fall and added to the compost bin.

Blue false indigo is a beautiful, long-lived, drought tolerant perennial with a robust habit and attractive steel blue-gray foliage. In late May, its intensely saturated violet-blue flower spikes rise above 3-4 feet tall multi-stemmed plants with bluish-green foliage.

Baptisias are at their best in full sun and in moist, well-drained soils. Fertilize sparingly to avoid the plant from flopping.  If grown in full sun, you do not need to stake baptisia. Baptisia is heat and drought tolerant and rarely troubled by diseases and insects.

The single plant spreads slowly by rhizomes and eventually will crowd out neighboring plants. Divide clumps every 5 -7 years and share divisions with your gardening friends or start new plantings.