I was raised on a farm and my mother worked 2 large gardens. She grow and perserved everything we ate (except flour, sugar, salt). So I do know better but here's how my lazy ass grows tomatoes.
Buy a half dozen tomato plants. Fine a spot in the yard where the grass grows best. Punch 6 holes in the ground, insert plants and water heavily. Then pile grass clippings deep around the plants to kill the grass that's there and forget'em until the tomatoes are ripe.

I got one plant that has over 50 tomatoes on it right now. I do zoo-kini and squash the same way. If it gets a little dry, I water about once a week. The grass clippings help hold the moisture in the soil.