Insect
Grape Berry Moth
A small tortricid moth whose larvae attack grape clusters in three generations, first binding flower parts, then boring into green berries, then feeding in ripe fruit.
Symptoms to Look For
- Webbing binding flowers or young berries together in the cluster
- Green berries with entry holes turning blue-black prematurely
- Ripe berries shrivelling with frass-filled tunnels inside
Affected Plants
Grape
Organic Solutions
Bacillus thuringiensis spray
Apply Bt spray to grape clusters at each generation emergence, timed using degree-day models or pheromone trap catches.
Pheromone traps
Hang pheromone traps in the vineyard from May to track adult flight and time Bt applications to larval hatch.
Prevention
- Remove and destroy mummified berries hanging in the vine during dormant pruning
- Strip loose bark from trunks and cordons in winter to destroy overwintering pupae
Garden, by Willowbottom recommends only organic, wildlife-friendly solutions. No synthetic pesticides, no harmful chemicals - ever.