While it can be trained into a tree with a single trunk, smoke bush (Cotinus spp.), also called smoke tree, is more commonly grown in its natural, multistemmed bush shape. Smoke bush provides dramatic color with 1 1/2- to 3-inch colored leaves and interesting fuzzy puffs of fading flowers that resemble wisps of smoke. You can choose varieties in a range of leaf and flower colors and also enjoy fall leaf colors of yellow, orange or red.
Climate and Culture
Native from southern Europe to central China, smoke bush grows in U.S. Department of Agriculture plant hardiness zones 5 through 8 and grows best in full sun. The bushes thrive in poor and rocky soil, but will also grow in average garden soil as long as it is well-draining. Give your smoke bush moderate water, with a deep soaking every two to three weeks and avoid planting it where the soil remains wet.
Problems and Pluses
An easy-care plant, smoke bush does not need fertilizer and has no serious insect problems. It is slightly susceptible to leaf spot, rust and verticillium wilt, fungal diseases that are sometimes caused by poor air circulation, infected debris that is left on the ground or over-watering. To keep your smoke bush healthy, avoid the conditions that cause problems, or try a natural remedy, such as spraying a solution of 2 cups dried chamomile flowers simmered in 2 quarts of water.
Most smoke bush varieties grow 12 to 15 feet tall and add height and color to the back of a garden bed or provide visual interest growing alone as a specimen plant. If you don't mind losing some flowering capacity, the bush can be kept smaller by pruning two or three of the oldest branches down to the ground in early spring. Smoke bush also makes a dense hedge that you can keep pruned to any height.
The most often seen smoke bush is the purple-leafed common smoke bush (Cotinus coggygria), with purple "smoke puffs." Cultivars include "Pink Champagne," with green leaves and pinkish-tan puffs. The taller American smoke bush (Cotinus obovatus) grows from 20 to 30 feet tall and has blue-green leaves, while the hybrid of American and common smoke bush, "Grace," grows 15 feet tall with blue-green leaves tinged with purple and deep pink puffs.