Please can you advise on this problem. This happens every year after flowering when leaves appear, when can we spray the tree to prevent this and with what?
1 Answers
This sounds like blossom wilt disease, caused by a fungus that overwinters in buds and on cankers on the branches. The tree looks bad for a while but grows out. Feed with potash to harden the growth.
Its prevalence is related to wet summers, and it is more severe on some kinds of cherry tree. Not much can be done, A spray of Bordeaux mixture or similar in autumn at leaf fall and again in spring at bud break may help.
More at: https://gardenie.wpengine.com/gerrycategory/blossom-wilt-disease/?id=5726