I am sorry for this delayed reply to your gardening question. The spring rush has brought a deluge of questions and we are working hard to catch up!
That sounds like a fungal disease. It could be rust fungus. The following web site offers photos to check out this possibility and control suggestions:
I suggest you take a leaf showing the symptoms to your County Extension Office for them too look over and diagnose. With a more specific diagnosis they can recommend an appropriate control option.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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