Much like the regular maintenance of a home or car, proper sprinkler maintenance will help the system perform at its peak efficiency. First, and foremost, check your system several times throughout the irrigation season. Walk each zone while it is on to check for proper coverage, eliminate over spray onto sidewalks and streets, and to repair damaged heads, fittings and pipes. The complimentary Water Wiser workshop provides an excellent overview of irrigation and sprinkler maintenance best practices.
Start with a solid design
Do not mix rotors (gear-drive or multi-stream) and fixed spray heads on the same zone. These heads apply water at very different rates and they do not play well together. Fixed spray heads apply water much faster than rotors and therefore will need less time on the clock. Fixed spray heads will also run off much faster and tend to be more susceptible to wind drift.
Check the irrigation system periodically to fix and straighten the nozzles
Periodically turn the sprinkler system on during the day to inspect for maintenance issues. Sprinklers and drip systems can easily get clogged, mowers and foot traffic can misalign spray, and growing plants can obstruct nozzles.
Head to head coverage
Sprinkler heads should be placed in a square or triangle pattern to cover the entire landscape. The spray from each nozzle should reach all the water to the next nozzle (not meet in the middle.) If the nozzle is designed to cover a 15-foot radius, pull the spacing in a bit and install heads 13 to 14 feet apart. This will allow for variations in water pressure and wind drift. Inadequate head to head coverage is a primary consideration for the development of brown spots in the lawn.
Drip system adjustment
Drip emitters and distribution tubing tend to be more delicate than spray head nozzles and will need periodic maintenance. Clogged or missing emitters will need replacing and as well as tubing. Emitters will need to be adjusted for watering needs and size of plants. Established plants may need less water than growing ones. Emitters should be placed on the outside ‘canopy’ of a plant.
Spring start up
Even though the system was properly winterized, it is critical to check for leaks, cracks and other defects throughout the entire system. Walk the entire zone when turning on the irrigation system. Check for alignment and spray patterns that could have gotten disrupted by shoveling snow or changes in soil moisture. Look at the valve box to ensure voles or other critters have not chewed through wiring.
Adjust watering times each month (or more often)
Landscapes will need less water in the spring and fall when temperatures are lower and humidity is higher. During this time, two days per week may be adequate. While the watering restrictions dictate watering every-third-day, weather conditions may allow for less frequent watering. Learn about the watering schedule. Consider replacing your traditional timer with a smart controller that automatically takes weather conditions into account.
Manage the pressure
Too high of pressure will put undue wear on sprinkler systems and potentially cause breakage. Too much pressure will also cause misting of spray which increases water loss to evaporation and wind drift. Too little pressure can prevent sprinkler heads from popping up. See how to adjust water pressure.
Check how many gallons per minute are available at your site
You can quickly determine gallons per minute by seeing how long it takes to fill a five gallon bucket from your outside faucet. Design your system below this threshold leaving room for variations in system availability and indoor water use. Keep in mind, if you have 12 gallons per minute available, you do not want to create zones that require more than 12 gallons per minute. Any indoor use will negatively affect sprinkler performance.
Turn off the system when it rains
Or, install a rain or moisture sensor so you don’t have to turn the system on and off manually. This can be automated by using a soil moisture or rain sensor.
How long should I run each zone?
Watering deeply and less often will provide a healthier landscape. While it may seem appropriate to water the landscape every day during a hot, dry period, this actually creates shallow roots which are more susceptible to evaporation and will require even more water. To determine how deep to water, turn on the system and irrigate until you see water collecting or running off. If you need more water to keep the grass healthy, add another start time. Steeper slopes, heavy clay soil and traditional spray nozzles will require multiple, short cycles to avoid runoff. Check the run-time calculator for an estimated irrigation time and how to program for cycle and soak.