The smoke bush – Cotinus coggygria – is one of the most beautiful of large bushes/small trees. The name smoke bush comes from the unusual flowering habit. Large inflorences develop in late spring, with many small flower buds. Most of these buds abort, and a small, feathery plume grows in its place. En-masse, these give the appearance of purplish-grey smoke. A large specimen can be enveloped in this ‘smoke’, which can be long lasting, and gives an unusual and beautiful display.
Cotinus can be vigorous growers, but the respond well to be pruned back very hard. Pruning will encourage the brilliant dark purple new growth of the purple-leaved cultivars such as ‘Grace’. If grown as a multi-stemmed bush, they can be pruned almost to the base. If they are grown as a single trunk tree, they can be pruned right back to near the base of the branches. However, be aware that Cotinus flower on second-year wood, so pruning a complete tree every year will mean that you will never get to enjoy the ‘smoke’. A good compromise is to prune back 1/3 or 1/2 of the branches each year. This will enable you to keep the tree in shape and still get to see the wonderful flowering display.
Cotinus lend themselves to a variety of different design styles. They can work well in slightly less formal situations, and look stunning at the back of a border. In Autumn the smokey flower heads look great, especially near dusk. One idea Heather came up with was to plant them behind a group of artichokes, the silver leaves contrasting with the purple. Large purple-flowered Alliums could be added to finish a stunning display.