The OLLA is made of low fired, unglazed, porous clay. When it is filled with water, the water seeps out through the wall of the pot. The roots of the plants create suction to pull more water from the OLLA as needed. The roots will eventually grow toward and around the OLLA as seen in the photo below where an OLLA was removed.
For us, it was about conserving water. But, there are many other reasons to use an OLLA:
-If your water use is restricted.
-If you want to save time by watering less often.
-If you want to reduce your water bill.
-If you container garden.
-If you have a small area which is difficult to irrigate or gets sun all day.
-If you cannot water your plants on a regular basis (travel, work, summer home, etc.)
-If you don’t like to weed.
The OLLA spacing will depend on plant selection, soil type and temperature. But as a general rule, plant within 18 inches from center of OLLA or 12 inches from the outer wall.
This space will equal a 36” diameter circle around the OLLA.
Optimum plant spacing and distance will also be influenced by the root system of the plant. For instance, tomatoes have an aggressive root system, so placing them at the edge of the wetting area will allow ample room for growth. In a 4×4 above ground garden, 4 tomato plants 18 inches from the center of the OLLA work well (see diagram). The smaller the plant, the more one can plant around one OLLA. A little experimentation and your common sense will serve you well when deciding. If you have any questions, we’d love to hear from you. Our contact information is just to the left in the green bar.
See diagram below:
No. The OLLA is partially buried and filled with water. Plant OUTSIDE the pot.
Watch my YouTube video.
Also, check out some of these sites:
Clay pot irrigation for tomato (Lycopersicon esculentum Mill) production in the north east semiarid region of Ethiopia | Tesfaye | Journal of Agriculture and Rural Development in the Tropics and Subtropics (JARTS)
The OLLA is 13” from the bottom to the lid and 12” in diameter. It holds a little over 2 gallons of water.
This is determined by a few variables: how much water your plants use, soil type, temperature, and rainfall. We find filing our OLLAS 1-2 times a week is sufficient here in Texas. You’ll find the pattern for your area with a little observation. It is best, if possible, to keep some water in the OLLA at all times.
Bury the OLLA with enough of the neck exposed so that soil and mulch do not wash into the pot. We have found that leaving 2-3 inches above ground/mulch level has worked well.
You can use the OLLA with any plant, keeping in mind that the OLLA may crack if used with plants that have a woody root. For example, trees and shrubs put out a very strong, woody root so may eventually crack an OLLA. However, a cracked OLLA is still efficient, and allows for deep root watering in the established plant.
If you live in a climate that has hard freezes, you should remove the OLLA in the winter.
The lid prevents evaporation and keeps out mosquitoes, etc.
Yes, a liquid or soluble type that will not clog up the tiny pores in the pot. Use less than is recommended as the fertilizer will be going directly to the root.
Yes, when seeds or young plants are put into the ground, they will need topical water until the roots are established enough to draw from the OLLA. After that, the OLLA will do all the work.
Your OLLA will last several years. It is a clay pot, so some maintenance is required. You can clean your OLLA with a a 1:1 mixture of vinegar and water. Pour one gallon of water AND one gallon of vinegar in your OLLA and let it sit for a few hours. Use a scrub brush for removing debris on the outside. If you choose to leave your OLLA in the ground, we do not recommend putting the water/vinegar solution in your OLLA.