Often, Botrytis causes leaf spots on bedding plants when infected flowers drop onto leaves. Botrytis is readily identified in a humid environment by its sporulation. The spores are dry and are easily dispersed by air movement. Overhead watering and rain also disperses the spores because the force of the water droplet landing on a leaf creates a shock wave that dislodges the spores into the air. Spores also may be carried on the surface of splashed water droplets to adjacent or nearby plants.
Botrytis infection is favored by high humidity, moist conditions, and stagnant air.
Control of Botrytis includes sanitation, environmental modification, and fungicides. As you move infected plants around, Botrytis spores will be released into the air and land on nearby plants. This is why fungicides play an important role in Botrytis disease control. Spray a protective fungicide after the plants are free of blighted tissue. Consult your county agent or the Georgia Pest Control Handbook for specific fungicide recommendations for your particular plant.