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Pruning an overgrown cherry tree
Q Our ‘Cheal’s Weeping’ cherry tree has outgrown its spot in a side bed in the garden. How will it respond to hard pruning?
Martin Stephens (via email)
A By all means prune your ‘Cheal’s Weeping’ tree, but tackle it judiciously. The best time is from mid-July to mid-August when pruning cuts heal quickly. Cherries are never pruned in winter when spores of shoot-killing silver leaf (Chondrostereum purpureum) disease are released into the atmosphere. Spores of this fungal disease are prevalent in autumn and winter and can infect several deciduous species if they are pruned now. These include stone fruits including cherries, plums and gages, apricots, almonds, hawthorn and poplars.
Affected foliage develops a silvery sheen and affected branches may die and develop an irregular dark stain in their centre as well as bracket-shaped fungi on older wood.
Ideally, shorten branches over three years to minimise stress. Initially, cut back a third of overhanging branches to an accommodating length. Complete the job over the following two years.
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