I've just gotten my 10×20 greenhouse built and ready to use, but I'm learning I will need a lot more help keeping it warm enough to grow tomatoes and cucumbers year round in central Illinois. I was toying with the idea of a small wood stove on one end, and an electric heater/fan combo on the other end of the greenhouse to keep it warm, but will that be enough?
Picture of my cat, Ducky, inspecting the greenhouse for good measure đ
by ladyrachelbugmagic
2 Comments
So, you know how hard your house furnace works during the winter to keep your house at 68 or so when the weather is 10 degrees?
Now picture your house has no siding, no wood sheathing, no insulation, an no drywall, but instead, only has a thin plastic film. Obviously there is a size difference, but regardless, you will need to thoroughly insulate your greenhouse or you’ll be spending an arm and a leg to keep it that warm, especially throughout the nights.
Western Massachusetts with an unheated hoop house here. Tomatoes and cukes aren’t going to grow over the winter for you without raking up a huge heating bill. That doesn’t mean you won’t see signifigant benefits, though.
The winter benefits of an unheated greenhouse are twofold: shorter ambient temperature exposure at night and cover from frost. Last winter our greenhouse dropped to -11f overnight but because it cools slower than the outdoors, warms faster in the morning, and shields the plants from frost we were able to overwinter spinich, kale, beets, and almost had lettuce survive.
The extended growing season is really what you’re after, though. We had greenhouse cucumbers and cherry tomatoes in November and harvested the overwintered spinich in April. We even had potted peppers last through October.
I reccomend not spending the money on heating initially. Push the boundaries of the growing season for a few years first.