Drip Irrigation

A drip irrigation system is the most efficient way to water the oasis and transition zones of xeriscapes. For turf areas, a sprinkler system works best. These conserve both water and your time.

The goal of efficient irrigation is to encourage deep root growth. To encourage deep roots, plants need to be watered deeply and infrequently. It may take one to two years for plants to become established, during which time they must be watered regularly. Once established, plants in the oasis zone will continue to need regular watering, those in the transition zone will need infrequent watering and those in the arid zone can survive on annual rainfall.

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Drip Irrigation Systems

Irrigation systems provide water efficiently to your xeriscape when nature doesn’t. A properly designed system will deliver the right amount of water at the right time. You may want to plan irrigation even for the arid zones, to allow for new planting and times of severe drought. As you change your xeriscape and as plants grow, the drip irrigation system can be modified.

There is a lot to be considered when designing an efficient irrigation system for your xeriscape. If you plan to design your own drip irrigation system, you may want to buy a copy of the book to the left, Ortho’s All About Sprinklers and Drip Systems. It comes highly recommended and covers the subject without a brand bias.

Some of the more popular brands of home landscape irrigation systems include: Toro, Rain Bird, Raindrip, and Orbit. A complete drip system from any of them includes three groups of components: control zone, distribution, and emission. Fortunately drip irrigation systems are pretty standard and components can be mixed and matched. Differentiation comes from quality of materials and ease of use. Some products are manufactured to be reusable and others connect in a permanent fashion.

Drip Irrigation System TimerXeriscapes Tree Drip Irrigation Tubing

Xeriscapes Drip Irrigation System

Xeriscapes Tree Drip Irrigation

At the control zone where the drip system connects to your spigot, you will need to attach a backflow preventer, a filter, a pressure regulator and a water timer (optional). The backflow preventer keeps dirt and fertilizer from accidentally contaminating household water, should the supply pressure drop. Drip systems use “emitters” with small holes to deliver water to plants. Because these can clog, it is important to use a filter as part of your drip irrigation system. The filter prevents minerals from accumulating and blocking the emitters. Filters need cleaning or changing periodically.Drip irrigation systems operate with water at a lower pressure than the water coming from the spigot. A pressure regulator must be used to keep the drip system water pressure between 20 to 30 pounds per square inch. The pressure in most household water systems is between 40 and 70 pounds per square inch. If the pressure is too high or too low, the system will not operate properly and can leak.

Using a timer is optional, but recommended. Without the timer, someone must turn the faucet on an off manually. Once you set the timer, you only need to adjust it occasionally. Watch your plants to see if they are getting the right amount of water. In hot weather, they may need a little more. Be careful not to overwater. Too much water can make plants susceptible to diseases or even drown them.

The distribution components consists of half-inch tubing that forms the main line,quarter-inch micro-tubing branches to individual plants and connectors. There are practical limits to the length of half-inch tubing, depending on the gallons per hour (gph) flow rate and spacing of emitters; 200 feet from valve to end cap is a good estimate. Micro-tubing sections should be no longer than six feet. Gallons per hour per circuit are also limited. Output of emitters on the circuit should total no more than 150 gph. The recommended limits for micro-sprinklers are slightly different.

There are a variety of emission devices for drip irrigation systems. There are drip emitters, misters, in-line drip emitters, drip tape, micro-sprinklers, and bubblers. Each has a different flow rate.

Drip Irrigation System Planning

Before purchasing a drip irrigation kit or parts, know what you will need. Lay out the system on paper first. Make a copy of your xeriscape plan then draw the irrigation plan on that copy. To select the flow and timing of water delivery, you must know how much water each plant needs. Water requirements depend on the plant and the soil type. You also need to know the water pressure and flow of water from the source spigot. Determine how many separate watering circuits are required.

Measure the lengths of half-inch and quarter-inch polyethylene tubing and dripline you will need. Plan the number and types of emitters you will use. Put some “goof plugs” on the list, for holes you punch in the main line but don’t use. Note all the connectors, elbows, tees, stakes and end caps you will need.

For small, simple areas you can easily do it yourself. However, if you have a complex xeriscape with multiple valves for different circuits or if it seems too confusing, you can hire a professional landscape company to install your drip system. If you have your system professionally installed, be sure to ask about what is required to maintain the system as your xeriscape matures or you add more plants. You may choose to make straightforward changes yourself.

Take a look at the guides shown below for additional details. The pdf documents from several major drip system brands show how to design a drip irrigation system for your xeriscapes using their products.

For price information, you can see how much the different kits and individual components sell for at Amazon.com.

Drip Irrigation Product Guides (Free)
Rain Bird Drip Irrigation Guide Orbit Drip Installation Guide Raindrip Drip Watering Guide

Rain Bird: Creating Beautiful Landscapes, March 2003 (24 pages, 1.61MB, pdf)

Orbit Dripmaster: Installation Guide (32 pages, 18.83MB, pdf)

Raindrip: Drip Watering Made Easy, 7th Edition, March 2008 (48 pages, 2.94MB, pdf)
Drip Irrigation Products At Amazon.com

Rain Bird Products

Orbit Drip Irrigation Products

Raindrip Products