Answer: Unfortunately, based on your description I am not certain what is happening to your plants but it certainly doesn't sound good. It might be a fungal infection such as blackspot or a combination of problems. I would strongly suggest you work with your local county extension to diagnose the problem(s) specifically and based on knowing that, determine how to proceed. If a chemical control is needed, they will have the most up to date recommendations on what to use and how/when is best to use it. In the meantime, clean up any fallen leaves and put them in the trash, and avoid handling the plants when they are wet.
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