Question
Growth is good except fruit shows rot at bottom of the tomato only. Rest of tomato is OK??  Help I don't know what to do?  I live in Southern California.  Thank you.

Answer
Mike:

Fruit rot like this generally is a fungus or bacteria. I recommend that you spray with a general purpose fungicide. There is no hope for the one that is rotten. Pull it off and was the plant good before applying the fungicide.

Let me know if this works.

Best wishes for a better crop.

Don