Powdery gray fuzz on leaves, stems, flower petals, or fruit is a characteristic sign of this fungal disease, which is also called botrytis blight and botrytis fruit rot. Touching the infected tissue causes a little puff of spores to be released into the air. The fungus can attack a wide range of plants, but tomatoes, beans, raspberries, and strawberries are particularly vulnerable. Botrytis-infected flowers fail to open. Infected leaves drop off, and fruits rot. The fungus thrives in cool, moist conditions.

• Keep foliage as dry as possible by encouraging good air circulation. Maintain a generous amount of space between plants and keep them properly pruned.
• Avoid overhead watering. Use drip irrigation or soaker hoses to help keep foliage dry.
• Avoid touching plants when they are wet.
• During harvest season, inspect plants frequently. Pick off and destroy infected foliage or fruit at least every other day to minimize the spread of disease.
• Clean up plant debris thoroughly in the fall.