Answer: Have you recently transplanted the coneflowers? Often newly-moved plants suffer from transplant shock--during the transplanting process, the delicate root hairs are damaged and it take a while for the plant to replace them. If you have not recently moved them, then I wonder if you have extremely sandy soil that dries out quickly. Are they wilting already this year (in the cool weather we've been having?) Or did they wilt in the heat of the summer last year? If it was the latter, I would certainlyapply a thick layer of mulch to help conserve water. If they are wilting already, I would worry that their roots have somehow been damaged.
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