There are some seed mats and other systems available to warm soil. The greenhouse or environment above the seed tray can be surprisingly cool as long as the soil is warm. Seedlings need light-if grown in a house, they should be moved outside on warm days. Transplants take 4-8 weeks to grow. Early cool-season crops will probably need 6 weeks.
Tomatoes are usually faster than peppers or eggplants.
Melons may grow in 2 weeks, if it is very warm. Let us know if you need a copy. Commercial growers have to prune fruit trees and grape vines when their labor is available. However, for small growers or homeowners who have a choice, it is best to wait until just before bud break to prune. For most of us, that is mid-late February.