Colorful, Sculptural Branching
In winter there's not much to take your attention away from the structure or colors of trees and shrubs. You can appreciate them for their branching habits and bark, not just because they supply the "canopy" or "spatial enclosure" of the landscape.
Trees, shrubs, perennials and biennials that flower in January and February with evergreen foliage and berries have a significant role in enhancing winter gardens. However, as cold weather arrives, it's deciduous plants that begin the show with colorful stems; interesting branching habits; and lacy, peeling or mottled bark.
Here are some plants that are particularly attractive in winter:
Paperbark maple (Acer griseum) attracts me because the cinnamon-red bark is different than we are used to seeing on trees in this region. It peels at various times of the year, and exfoliated pieces can be as thin as tissue paper. It's a clean, disease- and insect-resistant small maple, growing about 20 to 25 feet in height, which makes it very desirable. Elevate lower limbs this season (six feet or lower). Prune just above the branch collar at the trunk, that is, above the widened area at the base of the stem.
Coral bark Japanese maples (Acer palmatum "Sango Kaku") have the most outstanding winter stem color I have seen on a tree. The red to orange-red color shows most prominently on younger stems and bark in cold weather. It has an upright growth habit and will attain 20 to 25 feet in height and spread 15 to 20 feet wide in maturity. We have one that receives about five to six hours of morning light and was only five to six feet tall 16 years ago. It was planted seven feet from the house, and our neighbor questioned why we were planting it so far away. Now it's 18 to 20 feet tall by 10 to 12 feet wide, coming into scale with the house, and is an eye-catcher that causes passersby to ask, "What kind of tree is that with the red branches?"
Japanese maples that haven't been topped or pruned into a ball are beautiful in leaf, but many can be more striking in winter. As they defoliate in fall, the graceful branching habit of many Japanese maples and the smooth flowing lines of low, cutleaf varieties become more noticeable.
River birches (Betula nigra) have a rough-textured, exfoliating bark with light gray to tan hues. The sloughing bark on 25- to 30-foot-tall trees is especially ornamental in winter. River birches are showy as multiple or single-trunk trees. They will grow wide, 20 to 30 feet, if planted in full sun, but canopies can be kept narrower by planting groves, three to eight trees, randomly placed eight to 10 feet apart. The peeling bark is particularly visible this time of year. Grazing the bark with bullet-style landscape lights is dramatic and will provide night garden effects. It's a good tree for entry drives or for softening the front of a large house.
Crape myrtles (Lagerstroemia hybrids) have trunks as handsome in winter as the flowers are in summer. Allow the plant to grow as a tree. Do not top to head back stems. Keep the number of trunks to three or four for maximum ornamental value. Smooth multicolored barks of various species show tones of red, rust, tan and beige. Horticulturist Don Egolf bred numerous varieties introduced at the National Arboretum for interesting bark, fall color and various sizes.
Crape myrtles are available in sizes that grow from three to 35 feet. Of the hardy varieties Egolf introduced, most have American Indian names. Natchez is one of the largest, growing 25 feet or more. The bark is a smooth, handsome red and brown, well-suited for winter interest. Pocomoke is an excellent flowering form about three feet high and wide, definitely a shrub form.
Kousa dogwoods (Cornus kousa) have long-lasting flowers in spring; large, red, edible fruits in summer; and maroon fall foliage. Their other interesting characteristic is all but forgotten until winter, when the browns and almost white tans of mottled bark become noticeable. Shade tolerant, extremely disease resistant and growing only 20 to 30 feet, this is a small tree that will fit most gardens.
Lacebark pines are a three-needle pine -- needles emerge from the stem in groups of three. Its multicolored bark is a rarity on conifers. If you have a lacebark, show the bark. Its lacy texture is an eye-catcher year-round, especially on mature specimens.
Contorted filbert, also called Harry Lauder's walking stick (Corylus avellana "Contorta") isn't noticed until its leaves drop. It can be a large shrub or small tree. In winter, its curly-stemmed, contorted branching habit is most noticeable, having a sculptural attribute that creates great winter interest in a perennial garden. Harry Lauder's catkins (male flowers) elongate in winter and the leafless, twisted twigs are decorated with miniature "tail-like" flowers in preparation for spring.