When should damson trees be pruned?

John will reply personally to all your gardening questions every week

- John Negus

Q I have been asked to help with some neglected and rather sick damson trees. Is it too late to prune them? They need at least a light prune.

Prue Edwards, via email

A The best time to prune a damson is in July or August after harvesting fruit. If you prune it now, there is a danger of cut shoots being infected with silver leaf disease, a fungus that causes leaves to become silvery and die.

I urge you, therefore, to postpone this job until next year. For the moment, boost the tree’s vigour by feeding it with 1oz (28g) per sq m of sulphate of potash.

Sprinkle it over the feeding root area which coincides with spreading branch tips, and water it in.

Reapply it monthly next year, starting in April and continuing until September.

When pruning, remove branches crowding the centre of the tree to improve air flow. Additionally, cut back dead, dying and rubbing stems to green, sappy, healthy tissue.