I am one the Cumberland Plateau and lately my garden soil temperature is getting over 70 degrees a few inches down. I put in a small block of Nothern Xtra Sweet Hybrid corn along with some dutch cabbage this past week. My potatoes growing in a container are all doing well.
I am still reluctant as last year we had a freeze in April. Last freeze date here is April 9-15. With daily highs pushing 80 degrees I just had to plant something.