How Do Sprinkler System Zones Work?

Editor’s note: This post was originally published in May 2013 and has been updated for accuracy and comprehensiveness.

Keeping your grass green isn’t always as easy as watering. In fact, watering your lawn can be surprisingly hard! You can’t just drag out a sprinkler and call it a day.

How often should you water? How do you know when the grass has had enough? Is it possible to water too much? What if you go out of town?

An automated sprinkler system might be the solution you’ve been looking for.

In this article, you’ll learn:

• Why sprinkler systems are worth the investment
• How zones work
• How to choose and plot the location of your sprinkler heads

Check out these quick takeaways:

• To get the most from your sprinkler system, let the pros take the lead on design and installation.
• Don’t use spray heads and drip irrigation lines in the same zone.
• Sprinkler heads arranged in rectangles and triangles work really well for most yards.

Sprinkler Zones and Irrigation System Design

Setting up zones for your sprinkler system means that each section of your yard will get what it needs. No more overwatering in one section and underwatering in another!

Zones for grassy areas

Grass vs. trees and shrubs. Most trees and shrubs do just fine with what Mother Nature provides. Grass, however, benefits from regular irrigation. Check out our blog on the best grass watering tips to learn about your grass and how to water it effectively.

Sloping areas vs. flat areas. Sloping areas need to be watered carefully. Make sure that you don’t overwater and cause erosion. Overwatering can also flood your lawn or wash away nutrients and fertilizers.

Shady areas vs. sunny areas. Shaded grass retains moisture better than grass in sunny spots. Because of this, you don’t need to water shaded grassy areas as often.

Each of these areas should be its own zone. If the area is too large, you might need a cluster of zones. Each zone will have its own valve. This lets you irrigate the zones that need water while leaving others nice and dry.

Zones for flowers and vegetables

Flowers and vegetables don’t need the heavy, wide spray of traditional sprinkler heads. Drip irrigation is a far better setup for garden beds. With drip irrigation, water drips at the base of the plants, close to their roots.

Sprinkler heads and drip irrigation should not be mixed in the same zone. If your yard includes vegetable and flower beds, give the beds their own zone with drip irrigation lines.

Selecting and Plotting Your Sprinkler Heads

Once you’ve mentally divided your yard into zones, the next step is choosing the right sprinkler heads.

This process gets pretty technical. To get the most out of your irrigation system, let the pros take it from here. They’ll know how to gather the information they need, like water pressure and gallons per minute. Irrigation specialists know how to take these measurements accurately. They can even account for changes in elevation as well as friction within your irrigation pipes.

How to plot sprinkler head location

In most cases, sprinkler heads should be laid out in similar formations.

Sprinkler heads capable of delivering wide coverage will spray water in 360-, 180-, and 90-degree patterns. Regardless of which kind you select, you’ll use the same principles to space them in your zones.

There are many different styles of sprinkler system heads. For more information sprinkler heads, check out our overview of sprinkler system installation.

Once you’ve chosen your hardware, your irrigation system designer may mention a few possible layouts. Here are a few common options:

Head-to-head coverage. Head-to-head coverage prevents dry spots. Sprinkler heads spray water in circular shapes. Arranging them without any spray overlap will leave patches of your yard without water.

Imagine three pennies in a tight triangle formation. The empty spot at the center of the triangle would be an area of your lawn where none of the sprays reach. To prevent these unwatered patches, make sure that the spray radius of each sprinkler overlaps.

Rectangular or triangular patterns. Rectangular or triangular patterns deliver water most efficiently. This arrangement achieves the most overlap with the least amount of water.

Rectangular patterns of sprinkler heads suit small- and medium-sized areas. This setup also works well for corners and long, straight perimeters. Triangular patterns are very efficient in large, open zones. Triangular setups are also great for irregularly shaped borders.

The Bottom Line

Sprinkler systems make keeping your landscape healthy so much easier. No more lugging around hoses or waking up before dawn to water the grass. Zones help optimize your system.

That bed of beautiful heirloom roses in your side yard has different watering requirements than the dogwood by the mailbox. Well-designed irrigation zones will deliver the right amount of water to each location at the right time.

Designing a sprinkler system that functions as it should and meets the needs of your yard is not an easy task. Consult with a professional. In the meantime, you can sit back and enjoy as your yard flourishes under the attention of your irrigation system.