Water-Wise Plants Irrigation Scheduling
Watering your landscape with an automatic irrigation system will likely be the single largest use of water in your home. You can dramatically improve efficiency by using proper irrigation scheduling techniques such as those outlined below.
In the best of all possible worlds your irrigation system would supply your landscape with exactly the right amount of water to keep it healthy. The system would shutoff when it rains and would increase watering times during dry spells. The perfect system would supply different amounts of water to different types of plants and would eliminate over-spray onto sidewalks and pavements. The perfect system would only run at night to minimize evaporation losses and it would alert you if there was a broken head or a stuck valve or some other problem.
Unfortunately, the perfect irrigation system does not exist. Some new technologies to control irrigation based on weather patterns are being tested across the country (see Irrigation Future Trends), but until these products reach the mass market, irrigation scheduling and clock programming is a regular chore for many homeowners.
Proper irrigation scheduling is a skill that surprisingly few have mastered. Many people don’t realize that they must change their irrigation program regularly as the seasons change. Ideally you should program your sprinkler clock weekly or even daily to maximize efficiency. But even monthly changes to the irrigation schedule will result in substantial water savings and improved plant health. You should turn the system off when it rains and make frequent adjustments to the timing of each zone so that just the right amount of water is applied. Few people have the time or inclination to take this micro-managing approach, so these tips are designed to help you maximize efficiency with your sprinkler system through sensible scheduling.
The biggest problems encountered are watering too much and too frequently. Many of the common turf grass and landscape shrub diseases are made worse by, or even may be the result of, watering too frequently.
Irrigation Scheduling Tips
Water At Night
Never Water if the Soil is Wet
The first basic irrigation scheduling rule is never water if the soil is still wet. The old rule for landscape care was "if it doesn't look right, water it". This is often the worst possible thing to do. Plants wilt for any number of reasons other than needing water.
When You do Water, Don't be Stingy
Cycle Your Sprinklers
Technical note: in large areas of turf you may not notice the run-off because the water doesn't run into a gutter or over a sidewalk, but runs off to the lowest area in the lawn. It's still critically important to prevent the run-off. If you don't, muddy, wet areas will result where turf diseases will thrive, mosquitoes will breed, and your mower will leave ruts.
Multiple Start Times
Table 1: Sample watering schedule
Start times: 12:30 a.m., 2:00 a.m., 3:30 a.m.
Adjust Your Schedule As Needed
Some sprinkler clocks have a rain pause button that enables you to postpone irrigation for a day or more. On other clocks it is easy to shut the entire system off for any period of time.
Some newer clocks also have % increase/decrease feature. This is a nice feature that enables you to reduce or increase watering across your entire system by a fixed percentage. This feature makes it much easier to adjust your clock for changes in the weather.
Consider a Rain Shutoff Device
For more information on irrigation scheduling visit: