Greenhouses built in colder climates will still require some degree of heating/temperature control. There are a few methods for providing temperature control efficiently...
Geothermal heating, Storage Barrels, Aquaponic systems, bricks & blocks, thermal blankets, straw and Mulch are all heat generating/retaining materials/methods which are often utilized in Greenhouses. Straw generates heat, especially wet straw. Straw can be used around the plants (see also Ruth Stout Method) and also can be used for the Insulation for north walls on the greenhouses. Geothermal is an innovative concept which takes the heat/cool from within the ground and circulates it within the greenhouse. Click on the link below for more information on Geothermal heating of a greenhouse. Often water in black plastic storage barrels is utilized for heat storage as they absorb heat from the sun during the day and release it slowly overnight preventing the temperature from dropping quickly within the greenhouse overnight. Aquaponic systems work on a similar concept. If the fish tanks or grow beds are lined with black plastic, it helps the water to absorb the solar heat and release it slowly throughout the night. Additionally, concrete blocks and bricks will absorb heat in the same manner and can be used as much as possible within the greenhouse plans for additional heat storage. See the video below for a Passive Solar Greenhouse using Geothermal Heating, growing Oranges in Nebraska. Very informative.
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