Culture
Easily grown in average, medium moisture, well-drained soils in full sun. Tolerates a wide range of soils except wet, poorly-drained ones. Prefers somewhat infertile loams, but performs well in poor, rocky soils. Sharp drainage is essential. Plants have shallow fibrous root systems. If bloom is desired, prune very lightly in early spring only as needed. If bloom is not a concern, stems may be cut back hard in early spring to a framework to induce growth of vigorous new shoots with larger than normal leaves.
Noteworthy Characteristics
Cotinus coggygria, commonly known as smoketree, is an upright, loose-spreading, multi-stemmed, deciduous shrub that is native from southern Europe to central China. It typically matures over time to 10-15’ tall and as wide. It gets its common name of smoketree (or smokebush) not from the tiny, insignificant, yellowish flowers which appear in branching, terminal panicles (to 6-8” long) in spring, but from the billowy hairs (attached to elongated stalks on the spent flower clusters) which turn a smokey pink to purplish pink in summer, thus covering the tree with fluffy, hazy, smoke-like puffs throughout summer. Bluish green leaves (to 3” long) are ovate to obovate. Fall color is highly variable, but at its best produces attractive shades of yellow, orange, and purplish-red.
Genus name comes from the Greek word kotinus meaning olive.
Specific epithet comes from the Greek word kokkugia meaning smoke tree.
‘Royal Purple’ is a compact, purple-leaved version of the European species. It is a deciduous, upright, loose-spreading, multi-stemmed shrub that typically matures over time to 10-15' tall. As is the case with all plants of this species, it gets its common name of smoketree (or smokebush) not from the tiny, insignificant, yellowish flowers which appear in branching, terminal panicles (6-8” long) in spring, but from the billowy hairs (attached to elongated stalks on the spent flower clusters) which turn a smoky pink to purplish pink in late spring, thus covering the plant with fluffy, hazy, smoke-like puffs throughout summer. But it is the foliage that particularly distinguishes 'Royal Purple'. Ovate to obovate leaves (to 3” long) emerge a rich maroon red in spring, and then gradually mature to dark purplish-red to purplish-black in summer. Foliage retains good color without much fading throughout the growing season. Cotinus is in the same family as and closely related to the sumacs (Rhus). 'Royal Purple' was raised at Lombarts Nursery in Boskoop, Holland. It was introduced into the U.S. in 1953. Synonymous with C. coggygria 'Kromhout'.
Problems
No serious insect or disease problems. Some susceptibility to leaf spot, rust and verticillium wilt.
Uses
Single specimen, group or mass in shrub borders or sunny areas around the home. Long-lasting summer smoke display makes this a striking accent plant. Also may be used as an informal hedge or screen (a smoke screen as it were).