Why do strawberry fruits rot in the garden?
Strawberry gray mold, caused by the fungus Botrytis cinerea, is the most common and serious fruit rot of strawberries. Prolonged rainy and cloudy periods during bloom and harvest are very favorable for this disease.
Fruit infections usually appear as soft, light brown, rapidly enlarging decayed areas. Under moist conditions, abundant gray-brown, fluffy fungal growth on infected tissue is visible, giving the disease its name. Other diseases such as Rhizopus rot, anthracnose, and leather rot also decay strawberry fruits, but gray mold is the most common.
Thinning out strawberry beds to provide better air movement and sunlight penetration helps reduce gray mold. In winter, removal of dead leaves and debris from the bed helps reduce the source of the fungus, and in turn, springtime infections. If fungicides are used, applications made during bloom are most effective; spraying as fruits develop and ripen is wasteful and ineffective. Contact your local Extension office for fungicide recommendations.