Disease of the week: septoria leaf spot of rudbeckia
Photo courtesy of Purdue University
The state flower has me in a state.
My rudbeckia "Goldstrum," otherwise known as the Black-eyed Susan, is overcome with black spots on all its leaves. They spread and grow, attacking the stem and turning the entire plant into a crispy dark mess.
This is the third year in a row for this fungus, known as septoria leaf spot, and it is spreading despite my best efforts. I have been removing the infected plants and treating the ground with a liquid copper herbicide. And I sprayed the new plants regularly as soon as they emerged. But apparently I was not attentive enough.
My answer: rip out the Black-eyed Susans and replace them with another variety next year.
I am growing less and less patient with finicky plants. If you are vulnerable to mildews, rusts, wilts or fungus, you are out of there.
I don't mind working in the garden, but I am not running a sick bay.