Sprinkler Solutions: Installing DIY Yard Irrigation

Underground irrigation systems are easy straightforward to install, even for DIYers. Bilanol/Shutterstock

Why is one home’s yard verdant green, while the others are browning all around it? Chances are the answer lies hidden in the soil.

An in-ground sprinkler system is the easiest way for a homeowner to water lawns, shrubs, flowerbeds, and other decorative plantings. Automated systems also apply water more efficiently than hand-watering or oscillating lawn sprinklers and significantly reduce the amount of water used. These savings on the water bill can be further increased by using well water (more on that in a bit).

Best of all, there’s a good return on the time, effort, and dollars invested. With underground PVC pipe rated to last more than 100 years, the grandkids (or the home’s future owner) will thank you. That brings up another important benefit: It adds to the home’s value and may help it sell faster, as most buyers today want a home that’s beautiful yet easy to maintain.

Easier Than Expected

While the actual trenching comes later—particularly if the ground is still frozen—it’s best addressed now, as there are some common misconceptions about the amount of work required.

Water the soil two days before digging to soften it. Trenches for the main line and lateral lines (that run to the sprinkler heads) can be dug by hand to a depth of eight to 12 inches. Check with the county for the recommendation. Also, lift the existing sod and set it to one side, piling the soil on the other side of the trench for easy refilling. When trenching on a lawn, plan on laying fresh sod over the closed-up trenches after the pipe is laid.

For a midsize or larger property—especially with a lawn—consider renting a trenching machine such as a Ditch Witch. Keep in mind that a trencher should not be used to dig up ground cover (as there are no handy replacement sod pieces as with lawns) or flower beds. It also shouldn’t be used on steep slopes or too close to buildings that may be damaged.

Plan Like a Pro

Installing an irrigation system starts well ahead of the first shovel touching the ground.

The best jobs utilize a detailed irrigation map that includes the house and other hardscape, such as driveways and patios. For smaller jobs, a plan may simply include the water source—city water or well/pump—and the lawn area, trees, shrubs, and other plantings. Call the local utilities or an underground service locator to mark the site with tiny flags to indicate important No Dig areas.

Gardena offers a free online sprinkler system planner for those who want to plan this project digitally.

After the basics are drawn, it’s time to add the sprinkler heads to the diagram, spacing them to provide adequate and slightly overlapping coverage. Typically, they should be no more than 15 feet apart to avoid dry spots in the lawn.

Sprinkler Styles

Pop-up heads are very popular as they stay out of the way of mowers and foot traffic when not in use, popping up when activated by water pressure to a 2- to 12-inch height, with four inches being a common height as it gets the spray above most mown grass. Six inches will get above taller ground covers, with 12 inches the right choice to reach yet taller plants.

They are available in full (360-degree), half (180-degree), and quarter (90-degree) sprays, as well as units that are adjustable from zero to 360 degrees. They can deliver a continuous spray adjustable from 8 to 15 feet.

Rotor models are available from 4 inches and up to 12-inch heights. They rotate within the set parameters, spraying larger water drops for a radius of eight to an impressive 50 feet.

Fixed spray heads on a PVC riser (often called a shrub stick) work well in protected areas, such as planting beds where they are not in danger from mowers, people, and pets. They allow for more targeted watering with their 360-, 180-, and 90-degree options and spray zones of 4 to 15 feet.

Bubbler heads are best for trees, shrubs, rose beds, or other localized areas needing deep watering.

Pre-Work the Plan

Normally, the process is to purchase the necessary components as determined by the detailed irrigation map, dig trenches, and then cut and connect the pipes as one goes along.

If you’re getting impatient waiting for the ground to thaw, get a head start by carefully double- or triple-checking the measurements and pre-assembling the irrigation system in sections. Use a tee connection at each corner and sprinkler location as needed, being careful to aim them all upright. Take each section outside and lay it in place atop the ground. Looks good? If so, use PVC primer and adhesive to firmly connect the pieces. Note that the sprinkler heads and risers (aka shrub sticks) are only screwed in, so they can be easily replaced.

It’s a fun basement or garage project that will save a ton of time come spring.

The Water Connection

Purchasing, assembling, and installing the piping yourself can save thousands of dollars. The second consideration is the water source.

Outside Faucet

Opting for a manifold (valve) supply system and an electronic controller that taps into an outdoor spigot does not typically require a plumber. Some even offer phone app control! But keep in mind the effect of attaching the irrigation system to the monthly municipal water bill.

The Main Line

A plumber should be the one cutting out a section of the home’s incoming water pipe—or making the connection near a basement water meter—and installing a shutoff valve to connect to a controller and manifold system. And, again, this results in water bills that can quickly add up.

Well and Lake Water

Pumping water from a well (whether DIY or professional installation) or lake water (a very easy DIY project) pays for itself over time because it eliminates water bills. A basic setup typically uses a timer and an indexing valve to replace the zones of a manifold system. Best of all, in many cases, a pump can be retrofitted to an existing irrigation system currently using expensive utility bill water.