Consisting of little more than a hole dug in the ground and covered with plastic sheeting, walipinis (underground greenhouse) are significantly cheaper than conventional greenhouses and are arguably more effective. First developed in the cold and mountainous regions of Bolivia, the walipini harnesses heat from a geothermal phenomenon called the thermal constant.
Soil four feet below the surface of the earth remains between 50° to 60°F, regardless of what the temperature is above ground. The walipini uses the thermal constant to regulate the temperature inside the greenhouse, keeping your garden warm in the winter and cool in the summer.
In fact, “walipini” is the Aymara Indian word for “warm place.” The beauty is its simplicity. The earth regulates the temperature inside the greenhouse and the sun provides light for the plants.
Dirt from the excavation process forms a berm around the edge of the greenhouse, giving the roof a better angle to catch sunlight, and allowing greater water control and temperature regulation.
A walipini makes the most of the available resources, enabling gardeners to grow all year long, especially in cooler climates.
Extensive guides offer instructions on how to build a proper walipini and providing various strategies for greatest success. Given you have the right location.
Since your garden will be between six to eight feet underground, flooding can be an issue. The water table needs to be at least 5 feet below the bottom of the walipini, especially in the wet season.
Underground wires, gas lines, water lines, and other obstacles may lurk beneath the surface, prohibiting many urban gardeners from using a walipini.
The walipini also needs clear access to the southern sky, which provides access to the most year-round light.
Given the right conditions, a walipini could be designed with the cannabis cultivation in mind. With proper ventilation and humidity control, you could make your walipini into your own underground Sea of Green.