Fungal disease

Grape Black Rot

A fungal disease of grapevines that spots the leaves and turns berries into hard, black mummies.

Symptoms

• Small, round brown leaf spots with dark borders and tiny black dots
• Berries turning brown, then shrivelling into hard black mummies
• Dark lesions on shoots and leaf stalks

What causes it

The fungus survives winter in mummified berries and infected canes, and spreads in warm, wet spring weather.

What you can do

1. Remove all mummified berries from the vine and the ground.
2. Prune out infected canes during winter pruning.
3. Train and thin the vine so leaves and bunches dry quickly.
4. Where it recurs, protective fungicide sprays from bud break can help; follow the label.

General guidance only, not a diagnosis. Check product labels and local rules before using any treatment, and ask a horticultural specialist if a valuable plant is struggling. See the disclaimer.