Irrigation Systems for Desert Plants

Palm tree

Farmers, ranchers and home gardeners employ a number of ways to irrigate plants in the desert southwest, from flooding fields or yards with water from irrigation canals to using highly efficient drip watering systems. Much of the produce in the U.S. is grown in the deserts during the winter, and because rainfall is unpredictable, irrigation is critical to bringing the crops to market or maintaining a landscape at public buildings and private homes.

Flooding

Flooding fields is an effective way to irrigate crops used by many farmers or ranchers. Water flows through a system of canals and---depending on the crop, natural rainfall and temperatures---ranchers open big valves that flood their fields. Farmers plant their seeds in furrows, and the water flows through the furrows, where it sinks deep into the soil to water the plants. The perimeter of the fields have banks that keeps the water in the field so it doesn't flow back to the canals or to surrounding land.

At one time, homeowners could use flooding for their yards to water the grass, plants and trees. Now that water conservation is critical in the desert, no municipality is allowing new homes to irrigate by flooding, although homeowners in older homes where it was built into the landscape can still flood their yards.

Drip Irrigation

Drip irrigation systems use rubber tubing of various sizes to supply water to the plants' roots. These are the most water-efficient systems to irrigate plants in the desert and can be virtually any size. Besides the tubing, they use emitters whose capacity is measured in gallons per hour.

There is little evaporation from the drip watering systems so they are popular in the desert, especially in residential and commercial buildings. They are somewhat difficult in large-scale agricultural operations because the maintenance can be high and the tubing and emitters have to be carefully spaced so the plants get water directly at their roots.

Automatic Sprinkler Systems

Automatic sprinkler systems are used by golf courses and residential communities, and at private residences and commercial buildings. The pipes are almost always a type of metal and they deliver water to sprinkler heads. These systems are on an automatic timer that can be adjusted for the season, or turned off if rainfall has been sufficient to water the landscape and plants.

Soaker Hoses

Soaker hoses deliver water directly to the plants' roots with little evaporation. Of all the ways to water the home landscape in the desert, these may be the easiest. They are simply laid on the ground, held in place by stakes, and water is directly piped through them. They are made from recycled tires and are porous so water leaks out. The flow depends on the water pressure.

Manual Watering Systems

Desert plants can be manually watered with hoses or with a sprinkler attached to the hose. Sprinklers that spray water into the air have higher rates of evaporation. Gardeners who use overhead sprinklers do so in early morning and at dusk to minimize the evaporation.

References

• Arizona Municipal Water Users' Association