We now have two different types of greenhouses. A pit greenhouse and a hoop greenhouse. Actually considered a high tunnel greenhouse because of the height. Regardless, there’s two different types. One with ground source heat and one unheated.
For years we have used the pit greenhouse and I have a pretty good idea of how plants behave in the pit greenhouse. But the hoop house is new. so it is research time. Elliot Coleman is my go to guru for growing in a greenhouse. Below are links to videos I found of value.
Raising fish, using compost as heating – Growing Power is no longer in business but they utilized some interesting techniques. To learn more download their archived press release from here.