I have grown tomatoes in Collierville, TN and as they start to turn from green to red, then develop brown/black soft spots that turn mushy. Do you know what the problem could be?
Shelby County Tennessee
What disease it is would be difficult to diagnose without pictures or more information about the disease timing and location on the fruit. Cornell University has a very good web page with pictures that you may find helpful.
The most common that I would investigate first are anthracnose, gray mold, white mold, and blossom end rot.
Your county Extension Agent or State Specialist at UT should be able to assist you in identifying and managing your problem.