My damson/plum tree (not sure on the variety, but the fruit are large for damsons, and small for plums) seems to be producing no fruit this year except for a very few yellow, flat, curly ones (big and small) which have black spots on them. They look like deflated balloons - not a pretty sight. This is the first year since I've been here that it has failed to produce anything - the last two years there have been absolutely loads. We've till now tolerated the odd curly-leaved bits of new growth without apparent ill-effects. We did forget to prune it this year though, so it's gone a bit crazy. Not sure how old the tree is. I note that the flowers appeared this year at exactly the moment when it got really cold and all the rain arrived, and they were all gone by the time the sun came out again, so I'm guessing there won't have been much in the way of pollination... Any ideas if the two are realted? Or what the cause of the first problem is? Alex.
Check out a problem called Pocket plums. Sounds like this is what you may have. As you say pollination was difficult this year with the weather. We normally get about 200 lbs of Damsons, but this year I cannot see any at all on any of our trees.
Although I hesitated at first to google "pocket plums" fearing a potential wind-up, you seem to be right. So many thanks indeed! Is there a way to award points on this forum? Anyway, back to the pocket plums... I wonder - is it terminal? Will pruning back all the branches holding faulty fruit or curly leaves eliminate the problem, or should I be thinking about a new tree?
No real need to do anything other than perhaps remove the damaged fruit to avoid Brown rot later in the year. It is a seasonal thing and next year with proper pollination there should be no more. We get a few every season and they do no harm to the tree. Have a look at the backs of the curly leaves and you may well find tiny aphids. They damage the leaf veins so the leaf curls over to protect the critters. We ignore them as we are not keen on spraying, but you could spray with a Horticultural soap, if you feel the need. Personally I am very reluctant to prune any Damson or Plum trees, the ope wound can lead to fungal infections.