Pots were plastic. I drilled holes about 5" up from the bottom, on the sides. Compost was a mixture of horse, cow, chicken, rabbit- very well-composted. Had a velvety texture. I added rabbit manure and a bit of liquid kelp. Mulched the plants with 6-8 inches of dried leaves and straw and added worms. In the past, I've tried to baby along plants that showed signs of early disease. Pinching, pinching leaves that had lesions or showed signs of yellowing/browning/curling. Last year, I went take no prisoners: any tomato plant showing signs of early disease got yanked up and into the garbage bin right away. Even if they were producing blooms! Ended up with 7 pots containing 1 plant each, 2 pots with 2 and 6 in my garden. Most of the tomato gardeners in my area gave up-I had a very nice harvest from heirlooms, as well as the hybrids. I did not prune, at all, and I did no foliar sprays, both changes from previous years.
Oh, and my best producers were Black Russian, Goose Creek, Bhn 1021, Amelia and Cherokee Purple.