At 7th Street Farms the Tomato Season begins in early March, when we sow our Health Kick seeds near the windowsill, placing them in individual compartments under a moist 1/4 inch of sphagnum peat moss. A layer of Plastic Wrap goes on top--then a few sheets of newspaper, to provide a little insulation from the direct rays of the sun, shining in from the southern sky.
We then make sure to look in on them from day to day, keeping the seed trays moist as needed. Within 7 days almost all the seeds will have sprouted, and it will be time to place them under flourescent lamps. We do our best to keep the lamps approximately 1-2 inches above the seedlings, adjusting the lamps as growth progresses. Our plants get about 16 hours of light a day.
Once the second set of leaves appear and are a good size (the whole plant no more than 3 inches tall), it's time for repotting. We use empty plastic yogurt or cottage cheese containers (32 oz.) "poked" with adequate drainage holes. Our media is a standard potting mix like "Supersoil" --which does the job just fine.
To re-pot our seedlings, we clip off all but the top leaves, and then bury the seedlings up to their "necks" with just the leaves sticking out of the soil. The part of the stem covered by soil will develop roots--the beginings of a large root system. The newly potted seedlings then go back under the lamps for another few weeks.
As the first week of April passes the plants should be ready to go outside. We hold off water and place them in a sheltered spot, out of direct sunlight to "harden" them off--get them used to the cooler outside temps, the shifting breezes, and the brighter light of the sun. We gradually let them see more direct sunlight, until by the third week of April, they are getting about 7 hours of direct sun a day. It's time to go out into the Tomato Bed.
Removing them from the plastic containers, we then bury the plant up to its upper set of leaves, the intention being to get those roots growing from the burried stem once again--more roots means more ability to grow. The planting hole has already been prepared with about a quarter cup of a good 5-10-10 fertilizer placed at the bottom with a layer of soil on top to prevent the delicate roots from getting burned.
We space the plants about 2 feet apart in rows 3 feet apart, and install a custom tomato cage which is supported by two lengths of 1/2 in. rebar, 180 degrees out from each other. We use Tomato Wire from a local hardware store and make our cages about 16 inches in diameter. The end result is 48 inches tall, and several of our plants actually grow higher than this by season's end.
It's best not to over-water tomatoes, nor to get water on the leaves. To do so will encourage fungal diseases. It's also a good idea not to splash soil up onto the leaves--just in case some infernal soil disease is lurking below. Drip irrigation is a good idea here--as well as some mulch liberally placed around the stem. We've found that clipping off low hanging leaves is also a good idea--only the original stem should touch dirt where it enters the ground.