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!
The black leaves are due to a bacterial or fungal disease. Fungicide sprays with Maneb or Mancozeb will help control this or you may wish to just pull up the affected plant and keep the ones not so susceptible to the problem. The bugs you are seeing can't be identified based on that description. I suggest you take some in to your County Extension Office to see if they can identify them and prescribe a control if one is needed. There is no charge for their service.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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