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!
It could be nematodes or a root wild fungus. I suggest you take a plant that is going downhill to your County Extension Office for them to look over and diagnose. They can then determine if any solution is possible and if so what to do.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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