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!
Your Gerber daisies are being attacked by a fungal disease known as mildew. You can control this with sprays containing the natural ingredient known as neem oil (Greenlight's Rose Defense is one example) or the synthetic product triadimefon (Bayleton is an example) which is partially systemic and lasts longer.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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