A gray fuzzy growth is often visible on the infected tissue if high humidity and low temperatures persist. This disease can be minimized by removing diseased or spent flowers as soon as they appear. Watering early in the day and avoiding wetting of flowers or leaves can be effective. Maintaining fairly high temperatures and improving air circulation are also helpful. Circular or oval greasy brown spots appear on leaves which rapidly become a deep chestnut.
Lesions are sunken with well-defined margins.
If the temperature is 65 F or above and the humidity is high, the disease progresses rapidly to the growing point, and plants droop. Sanitation is very important to minimize the spread of this highly contagious bacterial disease to healthy plants. Maintaining good air circulation and avoiding wetting the leaves during watering are also helpful. Heavily infected tissues can be excised. Control can also be achieved with the use of bactericide sprays applied as soon as symptoms are visible.