Smoketree br> A Cloud of Gossamer to Grace Summer Gardens br> By Kim E. Tripp br> The NCSU Arboretum (now the JC Raulston Arboretum) br> The leaves have all become full and green as the haze of summer softens the outlines of trees and shrubs. Distant Holly hedges appear closer to the garden while the familiar Willow Oak on the corner seems to fade into the horizon. In this season of soft and rounded forms, a beautiful, old-fashioned shrub brings its own special grace to the landscape. Smoketree, Cotinus coggygria, is a large shrub or small multistemmed tree whose panicles of flowers create a drift of pink gossamer that floats above the landscape like an elfin cloud. This marvelous effect is actually due to the thousands of tiny pinkish hairs attached to the flowers which are borne in delicate, branched clusters at the ends of the branches. Since the hairs are so tiny, each branch appears to end in a mist that is actually the cluster of flowers. Cotinus coggygria is native to southern Europe, central China and the Himalayas. It has been in cultivation since the 1600's and was a favorite of Victorian gardeners.
Smoketree can grow to 15 feet in height with a 10 foot spread. It has an open, spreading habit and will achieve a pleasing, upright oval shape if left unpruned. Older plants can be limbed up to create handsome, multistemmed small trees. Since Smoketree flowers on the new, current season's growth, it can also be cut to the ground each winter and handled as a woody cut-back shrub in smaller spaces or even in a perennial border. With this technique, growth can be amazingly vigorous with spectacular flowering on 3-5 foot shoots. The leaves are a medium green and can develop good fall color on some cultivars. Smoketree is hardy throughout the Southeast and as far north as parts of New England. It makes a beautiful backdrop in a mixed shrub border and can be incomparable in bloom when massed in front of dark evergreens. Both flowers and foliage are dramatic when cut and used for indoor floral arrangements.
Smoketree has no serious disease or pest problems although it can rarely be affected by some rusts, leafspot and San Jose scale. It prefers well drained, full-sun sites but performs well in many soils ranging from light sands to heavy red clays. In modern, water conscious gardens, its excellent drought tolerance is a wonderful advantage.
Propagation, both vegetative and from seed, can be successful but is tricky. Softwood cuttings should be treated with rooting promoter and rooted under mist. Rooted cuttings should be overwintered in the rooting medium and not potted up until the following spring. Propagation from seed is also not simple. Seed should be soaked in acid for approximately 1/2-1 hour succeeded by 3 months of chilling at 41F with a fall sowing of the seed followed by spring germination.
There are a number of available cultivars of Smoketree that have special characters well worth seeking out. Several cultivars have beautiful, deep burgundy-purple foliage with associated wine-colored flower panicles that are darker and richer than the type. The purple cultivars make a much bolder statement in the landscape than the light pink varieties. Their deep velvet foliage and burgundy blush of flowers is incredibly beautiful in combination with silver or blue-grey foliage plants like some of the willows or blue conifers. One of the best of the purple cultivars is 'Royal Purple' which can be so dark that the foliage appears almost black. 'Nordine Red' is a spectaular wine red cultivar which is exceptionally hardy and holds its color intensity better than others in the hot southern climate. 'Nordine Red' also has good orange and yellow fall color. Of the pink cultivars, 'Daydream' is one of the best with dense growth and attractive green foliage. 'Purple Splendor', 'Velvet Cloak' and 'Pink Champagene' are also good cultivars. In addition to these cultivars there is another species of Cotinus which is of special interest as it is native to the southern US.
Cotinus obovatus, American Smoketree, is similar to the common Smoketree but gets larger (to 30 feet) and has spectacular fall color ranging from brilliant oranges and purples to vibrant golds and carmines. It has beautiful grey bark and pink flower panicles that are as showy as the common Smoketree's. There is also a hybrid cultivar, called 'Grace', that is the result of a cross between Cotinus coggygria and Cotinus obovatus. Developed by Peter Dummler of Hillier's Nursery in England, 'Grace' has exceptionally long and massive flower panicles that can be as long as 14" and as wide as 11" and offers striking fall color. Unfortunately, 'Grace' is not yet avaliable in American markets.
As you drive along past older gardens and parks you may see Smoketree's delightful halo mingling with the afternoon's haze. Stop a minute to savor its graceful beauty and consider planting Smoketree in your own garden to add its gossamer blush to summer's soft cloud of richness. br>