In areas were the temps hit 100 and stay that way for weeks, tomato growing is sometimes tough in the ground, let alone in a container.
In the ground, mulch is a smart move (If you live in the desert or So Cal or San Jaoquin). Layering newspaper between the rows helps tomatoes keep producing.
Have you ever seen a tomato cook on the vine? Its depressing. Also, uneven moisture causes bud end rot and fruit drop.
Daisy