Programming your sprinkler system controller seems like it would be an easy task, right?
Well, yes and no.
Anyone can program their sprinkler controller. To PROPERLY program your sprinkler controller takes some knowledge your lawn's water needs as it changes throughout the season.
It's convenient to have an sprinkler system, but they can easily waste water (and money) if not programmed correctly. Properly scheduling your irrigation times and keeping up with regular maintenance is the best way to ensure that your sprinkler system is working efficiently.
The concept behind properly watering is to water deeply and infrequently. Watering in small amounts often promotes shallow roots and causes your lawn to be more susceptible to high heat and drought stress. It's best to water for longer periods once or twice a week.
Typically we schedule rotor zones twice a week for about 30-45 minutes each and spray zones for about 7-15 minutes each. Drip zones need to run longer, about 45 minutes or so.
Each system is going to have its own unique watering schedule, depending on design and layout as well as how good their coverage is. Turf generally requires about 1 inch of rainfall a week to do well.
Set Up a Basic Schedule
The first step to programming your sprinkler system is to determine its output or how long it takes to measure 1 inch of water. Set up some cups around your lawn and run your system long enough to measure 1 inch of water. Note the time it takes to achieve this measurement.
Now you can set your controller to water on a basic schedule. This is the amount of water your lawn needs during the hottest and driest parts of the summer (100% of its max water needs). This feature should be included with most sprinkler system controllers.
Determine if it is equipped with a "water budget" or “percent adjust” feature (this should be in the sprinkler controller box).
Set the "water budget" or “percent adjust” to 100%.
Now that you have set your controller's basic water schedule, you can adjust it to reflect your lawn's needs and local weather conditions by using the Weekly Water Number. This number is updated each Thursday, April-September
Adjust Your Watering Schedule
The best way to be as efficient as possible is to regularly adjust your watering schedules during the season. If you only set your sprinkler system controller once for the entire season, it's going to be watering too much or too little and wasting water and your money!
Most controllers manufactured today make it easy to set up a basic watering schedule and easily adjust it throughout the season.
You can easily make weekly or monthly adjustments using these steps:
Set the base schedule for each watering zone at 100%.
Adjust your "water budget" or “percent adjust” feature for each watering zone to the percentage that corresponds with the Weekly Watering Number.
For example, if the Weekly Watering Number is 1.27 inches you will adjust the percentage to 130% and the timer will increase times for all zones. Similarly, if the Weekly Watering Number is .72 inches you will adjust the percentage to 75% and the timer will decrease times for all zones.