Have black patches on some tom plants in the GH. Is it blight or what????? :o
Unlikely this early, especially after last year's drought, which will have diminished the quantity of blight out there considerably.
can't see it being blight, where are the patches?... leaves could be any number of things, stem would be blackleg I think...
You could have a look here you may find your problem
http://aggie-horticulture.tamu.edu/publications/tomatoproblemsolver/leaf/
Beet Armyworm!!! :o