I apologize for this delayed reply to your gardening question and hope it is still helpful to you. Black spots could be a disease or due to sooty mold because of scale or other insects. I suggest that you take a sample from the plant along with a photo of the plant in its growing location (if possible) to your County Extension Office to see if they can help diagnose the problem and recommend an appropriate course of action.
Thanks for the question. Best wishes for a wonderful gardening year in 2007. Please stop in again soon!
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