It is best to wait until May for tender plants like these. Even then, we still have a 30% chance of frost. I wait until after May 10th, and then plant my tomatoes in a cold frame which remains in place for about 3 weeks.
To keep my starts happy until planting time, I’ll transfer them soon from 4″ pots to #1 gallon pots, and keep them indoors under bright light or in the greenhouse.
