For info I've uploaded a photo of a section of rudbeckia stem that died from Verticillium wilt.
I'm in the UK. It looks like some nearby Eryngium are also affected. The RHS website has a list of susceptible plants.
Thank you for your replies. From additional research it looks like it's Verticillium wilt. There's no cure or treatment. I will be carefully...
I have three clumps of around half-dozen rudbeckia. One-by-one the plants are dying. The leaves turn browm and shrivel and so do the flowers. I...
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