A puff of smokebush
Smokebush gets its common name from its large flower plumes that look like a puff of brown or pinkish smoke over the foliage in late summer and early autumn. Some bushes can have so many flower heads that the whole bush looks like a cloud of smoke, but some kinds do not smoke much, or at all, and are grown for their beautiful foliage.
The main kind is Cotinus coggygria, which is native to southern Europe and eastwards to China. It is a hardy plant and mostly seen in gardens in the purple-leaved forms, such as 'Royal Purple' with purple leaves that turn to bright scarlet in autumn, and the variety 'Grace' is even more spectacular in autumn with a lovely clear red, especially if seen against the light. There are green-leaved kinds too, the best of which is 'Flame' with brilliant autumn colour in shades of orange and red.
Cotinus can get too large for a small garden and may need to be cut back, or can be pruned to be a small tree on a stem. Pruning can be done in late winter or early spring. To make a small tree, one or more main stems can be chosen to remain and all side-branches removed up to one metre, or a more bushy plant can be created by cutting back the longer shoots to about half their length .
The small tree form will make more smoke-flower heads. A third way of pruning is to cut back hard all shoots almost to ground level, which gives a mass of vigorous new stems with large deep purple leaves, treating the plant almost like a herbaceous plant. This is a good choice to make where space is limited and foliage effect is required.
Smokebush foliage looks great as a backcloth for perennial flowers in summer, suiting every colour, especially hot colours, such as red, orange and purple, and using dark-blue for a contrast.
Smokebush likes a really sunny spot on well-drained soil, not too rich. If they grow too strongly, the leaves lower on the branches may turn brown and fall early as growth goes into the young shoot tips. The best autumn colour comes after sunny weather.
Q: The tree was pruned hard a couple of years back but I'm not sure if it was done correctly. A lot of long new shoots appeared and only some are bearing fruit. Any help would be appreciated. L Whelan, Co Meath
A: When an old tree is hard-pruned, it grows back strongly, and the re-growth needs to be thinned out and some shortened back in July or August. Start by removing new shoots growing towards the centre of the tree and shorten or remove others if crowded. Repeat this summer pruning each year to keep it under control, and winter prune as well.
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