Last summer, the fruit from my cherry tree had pinpricks and I found tiny white larvae in some of the cherries, even though I had treated the tree with a spray. What shall I do?
I think you may have the spotted winged drosophila (SWD) fruit fly, which looks like a common fruit fly, except the adult male has a distinct spot on each wing. While the common fruit fly is harmless to fruit with undamaged skin, female SWDs pierce the skin of cherries and other fruit to lay their eggs.
As an organic gardener, I would never advocate using pesticide sprays; the best method of reducing these flies is to trap and monitor them early, before they get to your fruit. You can buy specialised traps and attractant from Agralan ; you’ll find advice on how to place the traps on the Agriculture and Horticulture Development Board website.
You could also monitor around the tree using yellow sticky traps; these catch all flying insects, but allow you to correctly identify the fruit fly. The main SWD flying period seems to be July to October, but it is worth getting traps set up way before then.
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