When Can I plant my dahlia bulbs I believe I am in zone 7 greensboro NC
Dahlias do not like cold soil and they are sensitive to frost. Like tomatoes, putting them out before soil temp. reaches 60 F. isn't recommended. Tubers will not sprout in cold soil and run the risk of rotting. Knowing your zone doesn't tell me your last frost date but you can easily look that up online using your zip code. Your state's cooperative extension service is a good source for information about gardening in your region.