A copper based fungicide spray should help control it somewhat. Daconil would be preferable, but you said 'organic'.

Limiting any overhead and evening irrigation that you might be doing would also be helpful, along with mulching, if practical on the scale that you're growing at.

Here is a link that might be useful: Anthracnose controls

I searched to see if Serenade would work for Anthracnose and didn't find anything that was definitive. At any rate, it does look like it is used with copper:

· Serenade ASO (EPA 69592-12) (Bacillus subtilis, biological) OMRI (AgraQuest); Field use EB, LB, PM 4-8 qts/A; Bac. Spot, 2-8 qts/A combined with registered copper. 0 DTH.

· Serenade MAX (EPA 69592-11) (Bacillus subtilis, biological) OMRI (AgraQuest); Field and Greenhouse Use Bac. Spot, Speck EB, LB, Gray mold, 1-3 qt/A. 0 DTH.

Serenade is a biological control. Maybe this link will help.

Cindy

Here is a link that might be useful: Tomato fungicides