[virgil]

Thanks Diana! Maybe I should get a thermometer. 😀

[Pollard]

Hours and intensity of sunlight is an issue for Winter growing. Days are shorter because the sun is at a lower angle which also makes it less intense, hence the cold.

There's a youtube channel by a market gardener in KY that I watch. He says that even the cold/shade tolerant plants will stop growing in at some point in Winter but they'll stay alive for continued harvest as long as it doesn't get too cold. Row covers at night or on really cold days will help keep things alive.

They're best thought of as season extenders.

Personally, I doubt I'll want to walk out to the high tunnel when it's 20 degrees and windy outside possibly with snow on the ground. I'll go out and knock the snow off when/if needed but then it's back to the wood stove.

To heat a greenhouse, you either need a glass house or double layer of poly but even then, you'd probably pay more to heat it than the cost of the veggies.

[Diana in Wisconsin]

I have an indoor/outdoor one so I can see the temp in the greenhouse - whenever. Right now it’s rainy and 35 degrees, but it’s 55 in the greenhouse - even without any sun.

Meant to add that it ran us about $2,500.00 total between the kit we bought and gravel we needed to level a spot (we’re in The Driftless - hills, hills and more hills!) and lumber to build terraced beds around the house on the south side. It was an impossible incline for me to how, so that solved that problem.

Beau did all the work with his skid steer, I helped lay the gravel and did all the grunt work and clean-up, and we only had ONE fight while we put it together, so all in all the project was a success! :)

[Diana in Wisconsin]

Here are a bunch of unheated greenhouse ideas, rated by Family Handyman:

https://www.familyhandyman.com/list/best-greenhouse-kits/

Ours is similar to # 1, but I’m DROOLING over # 2! :)