Get a few plastic drums and paint them black if they aren't already. Fill them with water (reseal them) to store the heat energy and place them in a sunny spot in the greenhouse. They will soak up the suns rays during the day and then radiate heat at night...
Make benches using these drums as the legs. It helps to save space and you can work on the benches when replanting, etc.
Make benches using these drums as the legs. It helps to save space and you can work on the benches when replanting, etc.