Build an Earth-Sheltered, Energy-Efficient Greenhouse

Triple the length of your growing season with this simple, energy-efficient greenhouse design.

Prolonged Grow Season
To water or weed the plants, I had to open the pit and expose them to the air. Most plants will not grow in temperatures lower than 40 degrees; so, on a 30-degree day I was destroying the cozy, sun-baked 50- or 60-degree environment, shocking the small starts.
Photo by Fotolia/ngarare