Fungicides must be applied in advance of the disease as a protectant. Pesticides registered for use include copper, captan, chlorothalonil (Daconil), mancozeb, maneb, sulfur, and thiophanate methyl (Cleary 3336). Depending upon the susceptibility of the plant to this disease, spray every 10 days with a fungicide. Water early in the day so the plants have enough time to dry off completely.ĥ. Water on foliage and flowers from overhead irrigation, especially on cool, cloudy days, promotes the disease. Get a soil test to guide fertilizer practices.Ĥ. This can cause tender growth that is very susceptible to the fungus. Avoid fertilizing with excessive amounts of nitrogen. The fungus thrives in areas that are cool and moist and where plants are overcrowded.ģ. Give adequate space between plants to allow for good air circulation. Remove and destroy all infected plant parts as soon as they are observed.Ģ. The fungus is capable of invading tissue during all periods of the growing season and multiplies rapidly in declining foliage, hence, the need for good sanitation.ġ. Fungal mycelial strands (web blight) from previously infected plant parts can grow onto healthy plant parts and infect them. In the spring, spores form and spread by wind or splashing water to infect dying, wounded, or extremely soft plant tissues. Affected parts may be covered with a gray mold following damp, cool weather.īotrytis fungi overwinter as sclerotia on dead plant debris in the garden. Soft, brown spots appear on leaves, stems, and flowers following a cool damp period. Flowers may have irregular flecks and brown spots older flowers tend to rot quickly. This disease is the primary cause of decay in cut flowers.īotrytis blight causes buds and flowers to develop abnormally and turn brown. The extent and severity depend on weather conditions and cultural practices.

It affects the buds, flowers, leaves, and bulbs of many plants including African violet, begonia, chrysanthemum, cyclamen, dahlia, geranium, lily, peony, rose, and tulip.

Botrytis blight, also know as gray mold, is a fungal disease caused by several species in the genus Botrytis.

Botrytis blight on chrysanthemums