One of the great ironies of the green industry is that most folks that have an automatic sprinkler system do not water properly. It’s not because they don’t care, mostly it’s because they were never taught proper water techniques.
The sad but true fact is that a majority of people installing sprinklers have little sense of how to most efficiently water your lawn and landscape. In the interest of science, I ask you to do this little experiment: randomly call ten sprinkler companies and ask how you should best program your sprinkler system to water. Odds are that, most of them will have the same spiel, “set your rotor zones for 20 minutes and your sprays for 10 then run it every third day. If it gets hot, go every other day.” No concern for full sun, shade, slopes, etc. Watering this way is a terrible idea.
That ends today! I will lay out for you the perfect way to set up your sprinkler. First, realize that all sprinklers water faster than the soil allows the water to soak in. Watering past this point is wasteful (water running off the target area) but rarely will this much water penetrate very deeply into the soil. Our objective is to water deeply and infrequently with as little waste as possible.
The tools you will need are a watch, a screwdriver, a lawn chair and your favorite hot weather beverage.
Step One: Observe Your Sprinkler
Start with a semi-dry lawn. Turn on zone #1. Note the time. Sit in your lawn chair and run the sprinklers until the point of puddles forming or runoff into the driveway or street, then shut it down. How long did that take? That will be the maximum run time for that zone. To check the depth water was able to soak into the soil, use your screwdriver as a probe in several spots. How deep does it slide in easily? Make note of run time and average depth. Repeat for each zone (note: if your system is larger than six zones, you do not have to get a 12 pack… pace yourself).
Step Two: Decide Your Sprinkler Zones
Now that we know the length of time each zone should run, we want to figure out which zones should be grouped together. Almost all sprinkler controllers have separate programs (usually program A, B and C). Are there any zones that need drastically less water (examples would be the shady side of the house or shrub zones)? Group these on program A. Are any of your water penetration measurements extremely shallow (example would be ½” compared to 1-2″)? These are probably steeper slopes or areas of compacted soil. These zones, if you have them, should be grouped on program B. The remaining zones, set to Program C. Finally, set each program to begin watering at 4 a.m. every third day (Day #1 program A, Day #2 program B, etc.).
Step Three: Seasonal Adjustments as Needed
Now that the initial program is set, the only thing left to do is monitor your lawn and landscape when you get into the heat of summer. When any of the areas begin to show signs of drought stress (where the water penetration is most shallow will probably show signs of drying out first, program B in the above example), simply add a second start time to that program. This allows the first watering cycle that started at 4 a.m. time to soak in (limiting wasteful runoff) before watering a second time at 5:30 or 6 a.m. Not only will this save water but it will stimulate deeper root growth making your lawn and landscape more resilient.
Get it? Got it? Good.
Feel free to reach out to our team of certified irrigation technicians if you have additional questions or concerns about sprinkler system programming and water conservation. BG Outdoor Services has designed, installed, programmed, maintained and repaired lawn sprinkler systems in NOVA for over 30 years. We’re here to help, and happy to assist with your lawn sprinkler installation, upgrade or maintenance needs. Contact us today to learn more.
*Image courtesy of Rain Bird