Everyone loves fresh garden tomatoes, but the garden centers only seem to stock the run-of-the-mill varieties. Gardening catalogs are brimming with old-fashioned heirloom varieties that make you salivate, but they only carry seeds. There is really only one thing to do if you really must have that tomato of your dreams: grow it yourself from seed. For best success, always buy seed from a reputable source, use sterile potting soil and start with clean containers.
Dampen potting soil with warm water before planting. Let stand a few hours or overnight to distribute water evenly throughout the bag---you want it to be just moist, but not wet.
Fill containers with soil, compressing firmly,to a level sufficient to keep soil in. Make an impression about ¼ inch deep for each seed to sit in.
Drop one seed into each hole and sift dirt lightly over the surface. Press to firm soil. Do not water the seed further.
Place pots in a warm location out of the light--seeds germinate best in the dark. According to Gary Ibsen at Tomato Fest, "If temperature is kept consistently and sufficiently warm, your tomato seeds will usually germinate within five to 10 days. Best to keep temperature range 70 to 80F (21 to 27C). The lower the temperature the slower the germination. ... temperatures below 50F (10C) or above 95F (35C) are poor for germination." Water from the bottom as needed to keep soil barely moist until the seeds sprout, or place in a loosely fastened plastic bag.
Set seedlings under a good light source (preferably full spectrum grow lights, but ordinary fluorescents are adequate) placed a few inches above tops as soon as seedlings emerge. Placement is important--too close and lights may burn delicate seedlings; too far away and plants will be leggy.
Turn a fan on seedlings as they emerge---mild breezes promote sturdy stems. Wind dries soil, however, so check regularly and water as soon as the surface feels dry to the touch.
Harden off seedlings starting one to two weeks before transplant to garden. Place them in a protected location for a few hours each day, increasing exposure time until they sit out the full day. Bring in or protect at night.
Transplant seedlings to garden when all danger of frost is past for your climate zone, being careful not to disturb the roots. Set seedlings at same soil level they occupied in pots. Water well.