How to Manage Pests

Pests in Gardens and Landscapes

Botrytis fruit rot (Gray mold)—Botrytis cinerea

Flattened black masses of sclerotia appear on the canes of Botrytis-infested caneberry plants in late winter. In spring, sclerotia germinate to form masses of spores. Opened flowers may become infected, and the fungus will sporulate on the blighted flowers. Infected berries left on the vine become mummified. In storage, white mycelia can cover infected berries.

Life cycle


To promote air circulation and quicken drying of plant tissue, allow berries to ripen in an open canopy. Open canopies can be created by heavy pruning to maintain a narrow row of plantings, removing the first flush of primocanes, minimizing nitrogen fertilizer applic ation, and controlling weeds. Training systems also help. Some red raspberry cultivars are partially resistant. Pick fruit during cool temperatures and refrigerate promptly. Remove fruit mummies and dead leaves before tying up fruit canes in the fall.

Botrytis spores covering fruit

Botrytis spores covering fruit

Statewide IPM Program, Agriculture and Natural Resources, University of California
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