Infection first appears as a general decline, yellowing, and wilting of the entire plant. This is usually followed by complete collapse of the plant. Brown to black lesions can often be seen at the base of the stem, usually at the soil line.
Control can be difficult once plants are infected so prevention is important.
It is helpful to avoid overwatering, especially in heavy soils, and to avoid watering directly into the crown area of the plant. Adequate spacing between the plants can promote good air circulation. Highly symptomatic plants can be rogued and removed since recovery is unlikely. Control can also be achieved with the use of fungicide sprays applied as soon as symptoms are visible. Among the compounds registered for use in Connecticut are iprodione and thiophanate-methyl.