Irrigation, Water Management in an Arid Climate

Water Management using ollas and drip irrigation. Recommendations for OneWintryNight, Sunset magazine, and Rachio's smart watering controller.

Irrigation, Water Management in an Arid Climate

As I write this, we are lapping at the shore of an atmospheric river fed by a pineapple express created by a bomb cyclone. I say at the shore as we seem to be on the edge of recent storms, but they seem to avoid our hill. So the irrigation of the garden continues to be important.

First a confession: I play way too much Civilization. By the hours played, I would be qualified by the calculations of Malcolm Gladwell to be a Civilization genius. 

What does that have to do with this article? In the game, you try to start by a river. Pottery is discovered before irrigation. 

In broad terms we think of irrigation as water moving in channels to our crops. We learn about the great civilizations that have grown along rivers such as the Nile, Indus, and Mekong, and the Yellow. Your ancestors may have diverted the rivers to irrigate crops (mine were living in caves in Britain). But at the same time people were moving rivers, for at least 4000 years, early communities were using unglazed clay pots to maintain soil moisture for their gardens and trees. They were using ollas to irrigate their plants. Olla is latin for clay pot, and it too can be used for irrigation.

Using an Olla for Water Management

Water is a precious resource. An Olla helps maintain water as a resource in your garden. 

Bury a narrow-neck unglazed pot with a wide bottom into the soil. Leave the top exposed. Fill the pot with water. Then use a small clay plate or stone to cover the pot to keep out pests and reduce evaporation. The hydrostatic pressure (the difference in water pressure between two zones) will draw the water out of the porous pot. Keep the pot filled with water and that area of the garden will have the moisture it needs. One interesting concept with this technology: If the soil is soaking wet, such as after an atmospheric river type storm, the hydrostatic pressure is reversed. The water will flow into the pot and the cycle will reverse if the soil dries.

Recommendations

You can find beautiful (the lid can be pretty) ollas on Amazon. I really like this small US company out of Wisconsin: https://www.onewintrynightollas.com/  It is a small business that has a great product. 

A good tutorial on using an olla from Sunset magazine is found here: https://www.sunset.com/garden/how-to-use-an-olla-to-water-your-garden

from Sunset magazine

Ollas are still widely used around the world. An interesting article from the Gallifrey Farm near Perth in Australia describes using a sealed system of ollas with a gravity feed. That could be used in places that allow the collection of rain water. 

In my Master Garden program at the University of California, I saw ollas in Riverside.

Second confession: I do not pay for water. At least not directly. Water is included in my association fees. My association fees also include a pool condemned by the county and a tennis court with small canyon size fissures. But the water works.

Water Management at the TownHouse Gardens

I use a combination of drip irrigation and misters at the Townhouse Gardens. The misters keep the plants clean which reduces spider mites. Spider mites are really tough on my tomatoes and eggplants. They like to in the dust of a dirty leaf. Clean leaves expose the mites to predators.

The downside of misters are wet leaves. Damp leaves are susceptible to powdery mildew. Therefore if you water the plants before sunrise, the leaves will be dry within hours in the sunlight.

My irrigation system has no ollas. It is a combination of pvc pipes, tubing, and valves controlled by a Rachio smart watering controller. The Rachio allows me to control my watering from anywhere in the world. It is also responsive to local weather as can be seen from this screen:

Water Management on my latest Gro-Cart. 

Parts:

1/4 inch Rubber tubing

1/4 inch Barbed tee

Misters

Wire mesh

Working with rubber tubing is a lot easier if the tubing is hot. I add boiling water to an old coffee mug. Hot tubes slide easily over connectors like the barbed tee. 

The misters slide over an end of a barbed tee. It also holds the tube to the 1/4 inch wire mesh. 

Then I used a staple gun to attach the mesh to the crossbar of the gro-cart: 

Do you have any suggestions for water management in your garden? Add them to the comments section.