Build a $300 underground greenhouse for year-round gardening

[Flaxbee]

http://www.treehugger.com/green-architecture/build-underground-greenhouse-garden-year-round.html
(video at link)

Growers in colder climates often utilize various approaches to extend the growing season or to give their crops a boost, whether it's coldframes, hoop houses or greenhouses.

Greenhouses are usually glazed structures, but are typically expensive to construct and heat throughout the winter. A much more affordable and effective alternative to glass greenhouses is the walipini (an Aymara Indian word for a "place of warmth&quot , also known as an underground or pit greenhouse. First developed over 20 years ago for the cold mountainous regions of South America, this method allows growers to maintain a productive garden year-round, even in the coldest of climates.