I set the new greenhouse up on my indoor back porch. Gets full Southern Exposure. I raised the greenhouse up on a low coffee table so all the shelves have access to light cause of the full length windows. Gonna try some winter sowing with Tomato seeds in gallon jugs as suggested above. I have a huge supply of jugs available to me from work. Right know the temp inside the greenhouse is 48 degrees and outdoor temp is 19. I'm thinking with a little sun the greenhouse filled with gallon jug greenhouses should warm up nicely.