What are the little ‘worms’ in my plums?

Beata, by email

APIPPA SAYS It sounds like you have an infestation of plum moth, Grapholita funebrana. The grubs, or caterpillars, are fairly plump and often pinkish, up to 12mm long, and feed hidden away inside the fruit. If you cut a plum open, you may see the channels that have been eaten in the flesh, partly filled with the caterpillar’s droppings. The caterpillars overwinter in silken cocoons concealed beneath loose bark or in other similar places.

Next year, you could try putting up pheromone traps in early May. These lure male moths onto a sticky area within the trap and may slightly reduce the number of males available to mate with the females – and so reduce the number of caterpillars that can tunnel into your plums. It’s also worth trying to encourage predators of the moths, including ground beetles, birds and hedgehogs.