Every once in awhile, I see a condition in Goldsturm Rudbeckia: The whole plant turns black, then brown -- almost as if it dried out. But, it doesn't seem to be caused by drought. Seems like it's a disease or a pest.
Anyone else seen this?
-David
Sudden Death on Goldsturm Rudbeckia
Not in Goldsturm, but my Rudbeckia 'Prairie Sun' did that for some reason. But only half of it. Thought it was very strange.
Joanne
I have seen it. Would say a disease like a wilt as a guess.
Never saw it on mine, which I've had about 8 years now.
Bet it's powdery mildew. Just make sure you clean up all the stems and leaves and throw them in the trash, not in your compost.
Might want to thin out your clumps next year to give them good air circulation.
Ugh I hate that powdery mildew! However that has never really stopped flowering for me...they still flower but just look ugly!