What is an OLLA?
An OLLA is an unglazed clay pot fired at a low temperature. This allows the pot to remain porous. The OLLA is buried in the ground with neck exposed and periodically filled with water. The water seeps into the soil at a rate that provides adjacent plants with a constant water source at the roots.
The olla method is an ancient technique of low tech, low cost irrigation used in various environments around the world. Clay pot or OLLA irrigation has been the subject of university research documenting the highly efficient use of water and increased plant yields.
OLLAS can be utilized for vegetable, landscape, and container gardening. OLLAS are especially useful in arid climates but can be used any time a steady and efficient water source is needed. Once in place, the OLLAS will typically require refilling a couple times per week depending on soil and weather. Using OLLAS, leaves the soil surface dry resulting in fewer weeds and no soil compaction, a significant drawback of surface watering.
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