#1. Tomatoes are very easy to grow from seed. You should start you seeds indoors using seed starting pellets. Keep the soil warm and dark until the seedlings appear. Put them on top of your refrigerator to keep them warm. It’s important to note that light/sun isn’t crucial until the seedlings have popped out of the soil. They usually poke their heads out of the soil in about 7-10 days.
#2. As soon as the tomatoes sprouts appear, move the plants to a brighter yet cooler location. This is where they’ll need the light to continue growing nicely. The best time to grow tomato seedlings is at about 70ºF during the day and no lower than 40ºF at night. This promotes strong root development.
#3. As your tomatoes continue to grow (4″ tall), transplant them to larger pots. Bury them a bit lower into the soil than you would most other vegetables.
#4. About 2-weeks before you plan to transplant them into the garden, you should begin ‘hardening‘ the plants a.k.a. getting them used to living outside and away from adult supervision. Move the pots outside in the shade during the day and then bring them back inside at night. This is the easiest way to get them to thrive and adapt to their current growing conditions.
This is a VERY IMPORTANT step. You should always ‘harden’ tomato plants before transplanting them into the garden. This even needs to be done with Tomato plants you would have paid for at a local nursery.