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Clay Pipes & Ollah Pots


You can save massive amounts of water in your garden by installing clay pipes and Ollah pots.

Olla irrigation is an ancient method that involves using porous clay pots buried in the soil to slowly release water directly to the plant roots. Here’s how it can be adapted for growing grains in the desert:

1. Selecting Clay Pipes:

  • Choose clay pipes that are porous and can gradually release water. Clay pots with small holes or unglazed terracotta pipes are suitable for this purpose.

2. Preparing the Clay Pipes:

  • Soak the clay pipes in water for several hours before burying them. This helps saturate the clay and enhances its water retention properties.

3. Burying the Clay Pipes:

  • Dig holes in the ground where you plan to plant the grains. Make sure the holes are deep enough to accommodate the clay pipes without protruding above the soil surface.
  • Place the soaked clay pipes vertically into the holes, ensuring they are stable and secure.

4. Planting the Grains:

  • Plant the grains, such as pearl millet, sorghum, or teff, around the buried clay pipes. Space the seeds according to the recommended planting distance for each grain variety.

5. Watering the Clay Pipes:

  • Fill the clay pipes with water until they are saturated. The porous nature of the clay will allow water to gradually seep out and be absorbed by the surrounding soil.

6. Mulching and Water Conservation:

  • Apply a layer of organic mulch around the planted grains to conserve moisture and reduce evaporation.
  • Mulching also helps protect the clay pipes from direct sunlight, preventing them from drying out too quickly.

7. Ongoing Maintenance:

  • Monitor the water level in the clay pipes regularly, especially during dry periods. Refill the pipes with water as needed to maintain consistent irrigation to the plants.

8. Adjusting Watering Frequency:

  • Based on the needs of the grains and the prevailing weather conditions, you can adjust the frequency of watering the clay pipes.

Olla irrigation using underground clay pipes is an efficient way to provide a slow and steady water supply to grain crops in arid desert environments. This method minimizes water wastage and allows the plants to access water directly at their root zone, promoting healthier growth and better water conservation.

Clay Pipes & Ollah Pots

Clay pipes – http://lavierebelle.org

Using Ollah Pots for Growing Melons – Step-by-Step Guide

  1. Obtain Suitable Pots:
    • Get unglazed pottery or terra-cotta vessels that can hold approximately 2.8 to 7.6 liters of water.
    • Opt for squat, pumpkin-shaped pots with thick flared rims, or other shapes can be used.
    • Make your own pipes: A pipe 25 to 50 centimeters long with an outer diameter of 8 to 10 centimeters and 1 centimeter walls would be a good size to start with. Sections can be made with slip joints that are easily sealed in the field, or they can be made with necks.
  2. Select a Site:
    • Choose a site with sandy soil (preferably not dense clay) for better water absorption.
    • Dig a hole approximately 76 centimeters deep and 114 centimeters wide, depending on the size of the pottery vessel.
  3. Prepare the Hole:
    • Mix compost, sand, biochar, and aged manure in the lower third of the hole.
    • Place a flat piece of clay, terra-cotta, or ceramic at the base of the hole beneath where you’ll put the pot.
  4. Position the Pot:
    • Set the pot on the saucer or tray in the hole to reduce water loss from the bottom.
    • Ensure the pot’s neck and top rim emerge 2.5 to 5 centimeters above the ground surface.
  5. Fill the Pot with Water:
    • Add approximately 7.6 liters of fresh water to the pot, without adding fertilizer or manure to the water.
    • If possible, use harvested rainwater from a nearby cistern or storage tank.
    • Place a cap, lid, or small piece of tile on top of the pot to minimize water loss.
  6. Plant Seeds of Melons:
    • Choose garden crops with fibrous root systems like melons, pumpkins, squashes, watermelons, etc.
    • Plant the seeds approximately 2.5 to 5 centimeters away from the outside of the ollas.
    • Water and fertilize immediately with manure tea, compost tea, or fish emulsion.
  7. Monitor Water Level and Nutrients:
    • Check the water level in the pot frequently and refill as needed.
    • Replenish nutrients in the soil around the pot according to plant growth rates.
    • Weed the area as required.
  8. Protect the Ollah Pot:
    • Mark or build low barriers around the buried pot to prevent damage from humans or animals.
  9. Suitability for Specific Crops:
    • Note that buried pitcher irrigation might not be ideal for all crops or settings.
    • Some vegetables, and virtually no grains, may not accommodate the required spacing.
  10. Consider Cost and Durability:
    • Seek out cheaper and more durable pots to make the technique more affordable for low-income gardeners and farmers.
    • Custom-designed ollas for buried pitcher irrigation can be costly (ranging from approximately ZAR 300,- to ZAR 500,-), making it prohibitively expensive for some.

By following these steps, farmers can use Ollah pots to efficiently grow melons and other crops, optimizing water usage and improving overall plant growth.


Here’s an interesting story from the book: Growing Food in a Hotter, Drier Land: Lessons from Desert Farmers on Adapting to Climate Uncertainty by Gary Paul Nabhan

“Dr. Kraenzel described his visit to a farm outside Juarez, Chihuahua, near the Samalyuca Dunes, a vast sandy area. There, in an area known as the yonland, the farmer grew thousands of kg of watermelons using minimal water. He used inexpensive, unglazed clay vessels called ollas, along with home-saved seeds and plastic water containers. The farmer filled the containers at a nearby well and transported them by mule or pickup truck to the ollas burried in the sand. Despite receiving less than 230 mm of rain annually and facing summer temperatures as high as 43 ˚ C, the farmer successfully harvested a salable crop of melons each year.

Later, Dr. Kraenzel learned from desert restoration ecologist David Bainbridge that using just 200ml of “olla irrigation” per plant, melon yields can reach 25 metric tons per hectare. This translates to nearly 11 tons of melons per acre using less than 100m2 of water delivered through the pores of clay pots.

Dr. Kraenzel praised this innovative water conservation approach by peasant farmers and emphasized the importance of taking keen interest in and documenting such traditional knowledge.” Exciting isn’t it?

Ollah pots made near Rundu

More info:

Thus we highly recommend reading the following books:

Gardening with Less Water: Low-Tech, Low-Cost Techniques; Use up to 90% Less Water in Your Garden by David A. Bainbridge

Growing Food in a Hotter, Drier Land: Lessons from Desert Farmers on Adapting to Climate Uncertainty by Gary Paul Nabhan.

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