The Walipini is an underground greenhouse developed for South American mountain regions over twenty years ago. It was made to allow for edible plants to be grown year-round, no matter how severe the winter got. Its cheap, simple, and could change everything.
Not everyone is lucky enough to live in a climate with a year-round growing season. Most of us have to wait for spring to replant our delicate greens or summer for our tomatoes and peppers. While this seasonal planting is effective and can still allow a family to eat off the land, an underground greenhouse could change it all and allow us to harvest in the dead of winter.
The greenhouse uses passive solar heating to keep the plants warm under its cover. The earth itself provides protection from the elements while plastic sheeting overhead allows sufficient sunlight to come through.
The Benson Institute describes it:
The Walipini utilizes natures resources to provide a warm, stable, well-lit environment for year-round vegetable production. Locating the growing area 6- 8 underground and capturing and storing daytime solar radiation are the most important principles in building a successful Walipini.
The Walipini, in simplest terms, is a rectangular hole in the ground 6 to 8 deep covered by plastic sheeting. The longest area of the rectangle faces the winter sun to the north in the Southern Hemisphere and to the south in the Northern Hemisphere. A thick wall of rammed earth at the back of the building and a much lower wall at the front provide the needed angle for the plastic sheet roof. This roof seals the hole, provides an insulating airspace between the two layers of plastic (a sheet on the top and another on the bottom of the roof/poles) and allows the suns rays to penetrate creating a warm, stable environment for plant growth.
In all, the Walipini costs around $300 to construct. In the first year of use, there is no doubt it would pay for itself in saved grocery bills.
Many of the problems with our food system and subsequently our health is centered on who is providing our food. When we no longer have to depend on grocery stores and giant food corporations, we dont only take back control of our dinner table, but of our health.
You can find a detailed guide to constructing the Walipini here ( via tv.naturalsociety.com ).