GreenlyApple blossom weevil: how to recognise and treat it
Pest
Symptoms
- Blossom buds that never open; the petals turn brown and stay closed like a dome-shaped cap.
- A small grub inside the capped blossom eats the bud from within.
- Small weevils 4–6 mm long on the buds in early spring.
- Few fruits set after a heavy attack; losses can reach most of the crop.
Organic treatment
- After flowering, tie bundles of hollow plastic tying tube tightly to the trunk as shelters for the young weevils.
- Collect the bundles in December–January, when the weevils are inactive, and shut them in a bag or box so the weevils die.
- Spare spiders, which prey on the weevils.
Chemical treatment
- Pyrethrins on the adult weevils early in spring, applied with plenty of water; check the product is approved in your country and follow the label dose and pre-harvest interval.
Reference information, not a guarantee. Read and follow the label of any product: dose, safety and the days to wait before harvest.
Prevention
- On a warm afternoon at bud burst, tap branches over a sheet to count weevils; 5–10 per 100 branches is the action level.
- Watch trees next to woods and hedgerows, where the weevils overwinter in the leaf litter.
- Shelters work best on young trees with smooth bark and few natural hiding places.
Plants it affects
Sources
Figures checked against these sources.