Sounds like you may have bacterial spot. It shows up mostly after heavy rains or in very warm, damp weather.
Clean up all infected plant debris from the garden and destroy it. The disease will persist from one crop to the next in the soil and on diseased plant parts left in the garden.
To keep it from coming back next year, only plant peppers or tomatoes (which it also can infect) in the same place in the garden every 3 to 4 years.
You can spray with a fungicide when the spots first appear, but you have to keep repeating the spray as often as the weather conditions persist, and I wouldn't do that to my edible