Plant seeds six to eight weeks before moving them into the garden. Use a disease-free growing medium. Plant seeds in trays, flats or individual plastic or peat pots. Individual soil pellets also can be used to start seeds. The biggest problem with home-grown transplants is not enough light, Dickerson said.
Transplants require eight or more hours of direct sunlight or else they become tall and leggy.
If necessary, supplement direct sunlight with light from fluorescent bulbs suspended 6 to 8 inches above the seedlings. Most vegetable seeds germinate well at daytime temperatures of 70 degrees and nighttime temperatures of 60 degrees. Plants grown in flats or trays can be transferred to individual pots as soon as they develop true leaves. Allow at least 2 inches between pots for good air circulation and to prevent shading. Hardening off simply means setting the plants outside in the shade for a few hours each day to help them adjust to the outdoor environment.