It could be Septoria but its spots are usually raised on the leaf surface sort of like bubbles and I can't blow the pics up enough to tell for sure. It could also be Bacterial Speck and bacterial diseases respond better to copper based fungicides. What has the weather been like cool and wet (fungus) or hot and wet (bacterial)?

One other possibility is flea beetles but I think it is a little too early for them even in Charleston. But given the weather this year they could arrive early. Look for them - tiny black hopping beetles - as the shotgun pattern of the damage is classic for them. Of course treatment for them is very different.

Personally I wouldn't pull the plants yet. I'd strip off as much of the affected foliage as possible and spray the appropriate treatment and then continue to monitor.

Dave

Thanks for detailed response. The weather has been mostly cool, clear and sunny, humidity not too bad. I will look for the beetles and start daconil, even if preventative. Thanks again.

On second thought, I will try to get you a better photo. The affected leaves are in a zip lock in the house. I will see if this iPad camera can do close- ups.