Soil Temperature is the true key for better and quicker seed germination. Soil Temperature is equally important when your plant seedlings. With the right soil temperature seedlings will quickly send out roots and become well established healthy plants.
To day my soil temperature at 4 inch depth is 48%. Time to plant cool weather loving crops like onions and garlic for fall harvest.
Here is a planting chart with some of the more common garden crops and the best soil temperature to plant.