Yellow, spotted leaves, and mushy fruit are common issues for potted tomatoes, especially in late summer. Plant your tomatoes correctly and avoid these issues altogether!
Incorrect Pot: Tomatoes have big root systems, and no amount of extra water or fertilizer will substitute for lack of space for the roots. I recommend a large tree pot. Five-gallon buckets are not large enough to have a happy tomato all summer. Once the roots grow to the sides of the pots, they are easily burned by the heat of the sun. You’ll notice this from excessive wilting, as well as dry edges and yellowing on the leaves. Ten to fifteen-gallon pots are best. Make sure that the pots have drain holes on