Underground Greenhouses are
Missing in Tennessee
Underground greenhouses or Walipini seem to be missing in Tennessee as illustrated by the apparently more desired above ground type .
Here is a picture of the above ground greenhouse at the University of Tennessee Agricultural Institute which looks more like a factory than a greenhouse.
Other than the case of three men who lived in Trousedale County, Tn in 2005 underground greenhouses seem missing. The men managed to build caves under their house approximately 250 feet long and equipped them with grow lights for their underground “Pot” farm.
Because of their misfortune in borrowing extra power directly from the power lines and a subsequent run in with the utility company they were arrested.
These above ground greenhouses are not as useful to people in under developed countries who prefer something called a Walipini in Bolivia.
Of course the UTIA greenhouse is used by the students as a class room, but is still all above ground and not taking advantage of the heat storage available to underground greenhouses.
Contrast it with the Walipini in this video!
The ones made in Bolivia are sunk into the ground so that the earth can absorb the heat produced by the sun passing through the plastic top. Plastic is used as it is much less expensive than glass, also much easier to apply and doesn’t mind earthquakes.
Since digging a hole is much less expensive than constructing walls, the Walipini is immediately a much less expensive undertaking. Many are scrapped together with what ever material can be scrounged for or recycled from other buildings.
There are Walipini being constructed in Europe, Nepal and many other countries.
One very interesting Walipini was in Romania built by a man who wanted to grow citrus trees.
Americans tend to build as a lean to on a barn as this one in Minnesota was done. There is also a kindle book with a program called The Zero Energy Thermal Mass Greenhouse / One Hour of Free Video Instruction.
An American has shared his construction videos beginning with video 1 through video 4 . Here is the first, when he was doing the heavy digging.
His soil is very rocky and a pick axe was necessary to do a lot of the digging. Also, he didn’t dig the whole underground greenhouse floor as low as some that are shown elsewhere.
However he reduced his workload by leaving a shelf of dirt to place pots and growing flats on. Some diggers dug it out, then put the soil in barrels and used the top of them as a shelf….
Now on to Video 3 as you can follow what he is doing in each video.
Harder work than you think. But beginning to look like a real greenhouse. Much neater than the greenhouse below. However, the one below is a true thermal sunken greenhouse built using the thermal greenhouse plan referenced above.
From what I read in several places is that it is better to keep the air space above the hole as small as possible so that extra heat generated is stored by the earth surrounding the hole.
The Greenhouse above used the dirt dug out of the hole to fill drums with dirt to go under the tables and along the walls to provide extra mass for heat storage during the day.
Since they do not heat this greenhouse in the middle of winter they tend to grow cold tolerant plants like broccoli and cabbage later in the season.
Sunken Greenhouse or Walipini… what ever you call it, if built right can provide extra food for a small investment in building materials.
Everyone seems to modify any plans they use to match their particular soil and location and preference as to what kind of planting arrangements they want to use.
From the above video is an excerpt from the video description about the origin of the Walipini.
On Nov. 27, 2009, my dad, David Allan, gave an extemporaneous presentation on the Walipini greenhouse methodology. One of the main principles involves embedding the greenhouse in the earth to take advantage of the earth’s constant temperature, to store the solar energy collected during the day. The Walipini was first developed more than 20 years ago by the Benson Institute in Provo, Utah; deployed in South and Central America. The success of those projects has spurred the parent organization, the Church of Jesus Christ of Latter-day Saints, to help sponsor deployment of the technology worldwide.
Deep Winter greenhouse featured by MPRNews is interesting because they used recycled gutters as hanging plant boxes. The Tree Hugger features a very detailed description with pictures of the Walipini and shows a much deeper penetration into the ground making the roof almost level with the ground as it was in the first video. In places where you have limited rainfall the slope of the roof can be much less.
From what I understand, if you live in an area of high winds, then the lower your profile, the better. Except roofers will tell you that high pitched roofs deal with high winds better, the difference is that the lower roof conserves heat more efficiently. Please leave a comment below if you enjoyed our trip and share.