If your plant is only lightly spotted, pick off and destroy the infected leaves. If spotting is severe in your garden, try some additional control methods. Control fungal leaf spots by spraying infected plants with a fungicide containing mancozeb, maneb, chlorothalonil, captan, or zineb. Bacterial leaf-spot organisms cannot be as easily controlled. Fungicides containing basic copper sulfate or zineb, or antibiotics such as streptomycin, will help control bacterial leaf spotting, if used in combination with good sanitation practices. Badly infected plants should be destroyed. After working with infected plants, wash your hands and sterilize your tools in rubbing alcohol. Keeping foliage as dry as possible will reduce spotting. Avoid overhead watering, and water in the morning to give the foliage a chance to dry quickly. When using fungicides, make sure your plant is listed on the product label. Use resistant plant varieties whenever possible.
