Ollas (Clay Pot Irrigation)
System
Ollas are unglazed clay pots buried in the soil and filled with water to irrigate nearby plants slowly. This method uses the natural porosity of clay to release water where roots can reach it. It is an old technique that can work well in small garden spaces.
How it works
The clay pot is buried with its neck at or just above the soil surface and filled with water. As surrounding soil dries, water moves gradually through the porous clay into the root zone. Plants near the pot draw on that moisture over time, which can help keep soil conditions steadier. A cover over the opening helps reduce evaporation and keeps out debris.
Best for
It works best in raised beds, small vegetable plots, and dry climates where slow root-zone watering is helpful. It is most practical for compact planting areas rather than large landscapes because each pot irrigates only a limited space.
Tips
Place ollas close enough to crops that their roots can benefit from the wetted zone. Refill them on a regular schedule based on weather, soil type, and plant size. Check occasionally for cracks or mineral buildup that could affect performance.
General guidance for US gardens. Watering needs vary with soil, climate, and weather. Page updated Aug 4, 2026.