Vine weevil beetles love to lay their eggs in pots containing compost. It’s the vine weevil larvae that do the most damage as they munch on the roots of pot plants. If they’re not caught in time, will kill the plant.
Biological controls in the form of nematodes are available to water onto the soil. But these nematodes don’t survive in colder conditions, however it’s worth trying at this time of the year for use on greenhouse plants.
Do check all your pots as well. Lift the pot, gently tapping the bottom and sides to loosen the contents. Then remove the soil and plant from the pot.
Before doing this, have either an old tarpaulin or empty plastic compost sacks laid out on the floor to contain any loose compost.
The other reason for doing this is, if vine weevil larvae are present, the soil is usually very loose, and the plant will often come away from the soil leaving the munched roots behind in it.
If you find vine weevil larvae, you must dispose of the soil separately – not on your compost heap. Then, thoroughly wash the pot before reusing.
You may be able to rescue the plant, but to do so you’ll need to wash off every particle of soil from the roots and repot in fresh compost. If you’re lucky the plant will regrow.