Hi, Nina. It sounds like your black-eyed Susans have a fungus. The most common treatment is to use a fungicide such as chlorothalonil. As for transplanting, the best time to do this is mid- to late spring, though even early summer would be fine. Good luck!
Hi, Nina. It sounds like your black-eyed Susans have a fungus. The most common treatment is to use a fungicide such as chlorothalonil. As for transplanting, the best time to do this is mid- to late spring, though even early summer would be fine. Good luck!