Me and my husband recently retired in Tennessee from Florida. We are city people trying to act country! Ha ha! I'm going to try to grow vegetables in the winter.  I do believe it's feasible. This greenhouse is very well insulated. Keeps the heat really good at night. I also included a small radiator heater. Stays about 65 at night when the temperature is 35 outside.  Very happy. Can't wait to grow vegetables in the wintertime. P.S. this was a beast to put together. Organizing all the wood takes about 3 hours but, it's worth it!