Early Blight with some other possible fungus issues as well. The treatment is the same for all - remove all affected foliage and regular application of fungicide of your choice.

Dave

Thanks, Dave. Which fungicide is best for early blight and still be organic?

No simple answer to that question. The organic choices are somewhat limited and results vary widely so it boils down to your choice of the options available. There are many discussions here about the various fungicides and their pros and cons.

Something copper-based works best IME but when gardening organically Early Blight is also just something we live with. When it gets bad enough you just pitch the plant and plant new ones.

The well-proven control is Daconil but it isn't organic.

Fungicides are not specific to a disease, just to all fungus caused diseases, so don't think of them as "a fungicide for Early Blight". The same fungicide works for all fungus diseases.

Nor are they cures. They can slow the spread but can only prevent if used from day 1 of plant-out.

Dave

I have both Daconil (inorganic) and Neem Oil (organic) concentrates. So there are choices.
I use Neem mostly on cukes and squash (Powdery mildew prevention and fight). I think Daconil is more effective fungicide on blight and similar disease prevention. Just yesterday I did an application of Daconile on my tomatoes. I will repeat in 2 weeks.