I should have a bumper crop of tomatoes this year. So far so good...... no rings , fungus , black spots or any other diseases. They love the hot humid days and nights.
I don't......I usually fertilize and rototill right before I plant the vegetables in the spring. If you can get your hands on some pure chicken manure....get it. It's much better than cow manure. But make sure you rototill your garden 6-9 months ahead of time because it will burn the roots and/or kill the plants. Or you can just buy the granular fertilizer and mix it in the soil in the spring.