In today’s world of GMOs and pesticides, there’s a growing need for safe and natural food.
Unfortunately, there’s also a reduced amount of space available to cultivate healthy, organic food. Weather extremes and harsh climates can also diminish our ability to grow food.
What’s the solution? An underground greenhouse.
Traditional greenhouses can be expensive to construct and difficult to heat. In contrast, underground greenhouses are both affordable and temperature-efficient.
What does an underground greenhouse look like? How is it constructed? And what are the benefits of building one?
Read on to learn more about this eco-friendly solution for food production.
What Is an Underground Greenhouse?
At most latitudes, if you dig down six to eight feet, the temperature is usually between 50 and 60 degrees Fahrenheit. In this ideal climate, plants can grow whether it’s sweltering or snowing outside.
The idea of an underground or “pit” greenhouse was first developed for the cold mountainous regions of South America. Known locally as a walipini (“place of warmth”), it allows farmers to grow crops year-round.
What does a walipini look like?
Generally, it’s a rectangular hole in the ground that’s covered by plastic sheeting. A thick wall of earth at the back and a much lower wall at the front provide the necessary angle for the roof. The plastic sheeting should face the winter sun, ensuring constant temperatures year-round.
Because of its underground design, the only real costs are the excavation, the glazing material, and the truss system on top. The original designers at the Benson Institute claim that most people can build a walipini for less than $300.
If you have access to earth-moving equipment, you’re one step closer to your own walipini. As an alternative, you could gather a group of friends or neighbors to help you dig.
However you construct it, an underground greenhouse is a useful and eco-friendly addition to your property.
Why Build an Underground Greenhouse?
A walipini may sound like an interesting addition to a healthy lifestyle, but is it worth the effort? Definitely!
Here are six environmental and economic benefits to an underground greenhouse.
We’ve touched on it before, but let’s dig a bit deeper (pardon the pun).
When you dig down even three or four feet, the temperature changes dramatically. Frost lines rarely extend past four feet. This means a greenhouse situated six to eight feet below the surface will be completely protected from frost.
Because you have all that thermal mass, it’s nearly impossible to lose warmth. Even if it’s 20 degrees outside, your plants will be safe and warm inside the walipini.
Good For Every Climate
Whether you live somewhere very hot or very cold, an underground greenhouse is a terrific way to grow your own food.
It sounds counter-intuitive that this design could work in a very cold climate. But some of the first models of underground greenhouses came from Canada, so the theory is sound.
In fact, walipinis are common in cool, high-elevation locales such as Ecuador and Nepal. They’re also common for gardeners in rural areas of China.
Granted, you won’t get balmy temperatures inside your greenhouse in the dead of winter. It will, however, stay much warmer than a traditional greenhouse.
Traditional greenhouses, like the ones designed by Cultivar, can be beautiful additions to your property.
But what if you have limited space or your neighbors don’t like the idea of staring at a glass structure? An underground greenhouse solves both potential issues.
If your property contains a hill, you’re already halfway there. Walipinis built into a slope are virtually invisible from a distance.
And if you love the all-natural look, you’ll love the interior appearance of your warm, earthy greenhouse.
Very Little Maintenance
Because traditional greenhouses have more exposure to the elements, they get worn down more quickly.
In contrast, the only exposed area of an underground greenhouse is the roof (and maybe a few beams). And because the garden beds stay sheltered from the rain, they’ll last longer.
Another bonus? You won’t need to spend as much time pulling weeds or watering your garden.
Weed seeds will have a difficult time penetrating the underground structure, not to mention you’re using virgin soil. And because walipinis hold moisture so well, you won’t need to water nearly as often.
Underground greenhouses aren’t limited to growing plants. They can also be a terrific place to keep small livestock.
You could build a large greenhouse with enough room for chickens, sheep, or goats. Or you could build a separate structure specifically for the animals.
This is especially beneficial in the winter when it’s important to keep your livestock warm enough. A walipini can serve as their “home” and keep them protected from the outside elements.
Protection From Pests and Chemicals
Perhaps the most relevant reason to construct a walipini is to protect your food from pests and chemicals.
Because the greenhouse is almost completely enclosed, insects can only enter through the open doorway or on your clothing. Deer, rabbits, and other animals will also be unable to access the plants inside.
A properly designed walipini will also keep out domestic cats, which often use gardens as their personal litter box.
All of us worry about what’s in and on the foods we eat. That’s only natural, given the scary headlines and statistics we’re bombarded with. By growing your own produce in a completely enclosed, protected environment, you’ll know exactly what you’re eating.
Even if you live in an area that sprays pesticides, your plants will remain safe. Wind and water will have no effect on them inside the underground greenhouse.
Final Thoughts on Walipinis
Perhaps the idea hasn’t gone mainstream yet. But it’s only a matter of time before more people embrace the idea of growing their own healthy food.
Who knows? Underground greenhouses could one day be the key to our very survival! With one on your property, you’ll already be one step ahead of the crowd.
Looking for other home improvement ideas? Be sure to check out our informative home repair section for fresh inspiration.