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!
Those spots may not be receiving adeaquate watering. They also could be diseases areas. Your County Extension Office can assist by looking at a sample you bring in and/or some digital photos, and helping to determine the cause. Then a proper remedy can be suggested.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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