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Fruit clusters

15 problems can affect the fruit clusters of your grapevine. Filter by type, or open one to compare symptoms and treatments.

All (15) Fungal (8) Insect / pest (3) Disorder (4)

Fungal moderate

Anthracnose

Sunken spots with dark margins on shoots and berries — the classic "bird's-eye rot".

Fungal moderate

Bitter rot

A late-season berry rot that softens ripe fruit and leaves it bitter — often riding in behind other rots.

Fungal high

Black rot

Tan leaf spots ringed with black dots, and berries that shrivel into hard black mummies.

Disorder moderate

Boron deficiency

Poor fruit set with "hen and chicks" clusters and dying shoot tips — common on dry, sandy soils.

Fungal moderate

Botrytis bunch rot (grey mould)

Fuzzy grey mould that rots ripening clusters, especially after rain near harvest.

Fungal high

Downy mildew

Yellow "oil spots" on top of the leaf with white fuzz underneath — loves wet, warm weather.

Insect / pest moderate

European grapevine moth

The main cluster caterpillar of European vineyards — eats flowers, then berries, inviting rot.

Insect / pest high

Grape berry moth

Caterpillars that web and bore into berries, opening the door to bunch rots.

Insect / pest moderate

Grape mealybug

Soft, waxy sap-suckers that foul clusters with honeydew — and spread leafroll virus.

Disorder moderate

Potassium deficiency

Scorched, curling leaf margins on older leaves and poorly ripening fruit — a heavy-cropping vine's shortfall.

Fungal high

Powdery mildew

A dusty white-grey coating on leaves and berries — the most common grape fungus almost everywhere.

Fungal moderate

Ripe rot

Reddish-brown circular rot on ripening berries, often oozing salmon-pink spores.

Fungal moderate

Sour rot

Clusters that turn to vinegar-smelling mush late in the season, swarming with fruit flies.

Disorder moderate

Sunburn & sunscald

Heat and intense sun scorching exposed berries and leaves — often triggered by over-thinning the canopy.

Disorder moderate

Zinc deficiency

Small "little leaf" growth and straggly, shot-berry clusters — a look-alike for fanleaf virus.