google light cyles or seasons for tomato and see they dont regulate to times like cannabis does
Tomato seeds germinate best at
80 degrees, and should be mostly up in 5 to 12 days. Remove any cover you may have on them as soon as they begin popping up. The fresh sprouts should be kept 4 to 6 inches under
fluorescent lighting. The light should be kept on 18 to 24 hours a day. When they are 1 1/2 inches tall, carefully transplant them into their own 6 inch containers.
Tomato Plant Care
The easiest step of how to grow tomatoes. Keep them under 2 or 3 fluorescent lights that you leave on
18 to 24 hours every day. I usually feed them Maxsea 16-16-16 at this point, although they could probably use even more nitrogen (the first number). The strength of the solution is about
600 ppm, which is 1 rounded teaspoon of Maxsea/gallon. I also add 10 ml/gallon Thrive Alive B1.The ideal temperatures for growth are
70-75 degrees during the day and 65-67 degrees at night. When the plants reach 12 inches or more, they may need
transplanting to one gallon containers. After 6 weeks or 8 weeks, your plants should be just about ready to begin fruiting them.
Begin Flowering your Tomatoes
Flowering is one of the trickiest parts of how to grow tomatoes indoors. You will need to be familiar with how to
force flowering in plants. Some tomatoes flower in 60 days and others take up to 80 days, beginning from the time you force flowering. Just as you begin this process, you want to make your
final transplant into 3 gallon containers.For the first
two weeks, you want to feed them heavy with a
10-52-70 or similar fertilizer. Each time they need water give them food also at
800 ppm, which would be a little over half of the recommended "full strength" on the directions. Keep in mind you are feeding them each time you water them. For the rest of the season, feed them
16-16-16 or similar at 800ppm.
http://www.jasons-indoor-guide-to-organic-and-hydroponics-gardening.com/how-to-grow-tomatoes.html