The amount of water your plants need and when it is needed changes with the weather, length of day, and root depth. By regularly adjusting the watering schedule of your automatic irrigation system (unless you have a smart timer), you can maintain healthy, beautiful plants and avoid wasting water.
In the Pacific Northwest, the watering season typically lasts from April through September. Check this page for advice on programming your sprinkler timer for the upcoming week. Interested in receiving weekly watering advice straight to your inbox? Sign up for the weekly water advice email! From March to October, we’ll send you a short email once per week that includes our watering advice and tips.
Weekly watering advice
Last updated: Friday, June 5, 2026
Conditions: It’s been hot! However, the soil may still be wet under the surface from recent rain, with more rain expected.
Watering recommendation:
- Established high-water-use plants: If the soil is dry beneath the surface, water once this week about ½ inch.
- Established deep-rooted plants with deep mulch: Do not water this week.
If you prefer having a green lawn instead of letting it go dormant, consider “mulch mowing.” Mulch mowing entails leaving grass clippings on the lawn instead of collecting them. The clippings decompose quickly, adding organic matter and nutrients to the soil and improving overall soil quality.
To mulch mow, set your mower to the highest setting. Avoid cutting more than 1/3 of the grass height at a time and leave the clippings on the lawn. Healthy soil supports a healthy lawn that needs less frequent watering.
Have questions about mulch mowing your lawn? Reach out to Mark.Guthrie@seattle.gov.
Resources
- Learn more about mowing lawns to conserve water
- Need some professional assistance? Check out this short list of local certified landscape professionals!
- If you’re interested in learning about supply conditions for Seattle’s regional water system, please visit Water Supply Conditions – Utilities | seattle.gov.
Choosing the right run time for your system
Each watering should apply a ½ inch of water. The application rate of a sprinkler system depends on the water pressure, system design, and system efficiency. Below are some general ranges of typical run times based on the precipitation rate of your sprinkler heads:
| Head Type | Nozzle Description | Run Time* for a ½ inch | If Using Cycles** | |
|---|---|---|---|---|
 | Spray Head | Sprays like a fan | 15-23 minutes | 3 cycles of 5-8 minutes |
 | Rotor Head | Single spray that rotates | 30-75 minutes | 3 cycles of 10-25 minutes |
 | MSMT Head | Multiple single sprays that rotate | 50-75 minutes | 3 cycles of 17-25 minutes |
**Cycling Recommendation: To prevent runoff and ponding in areas with clay soils and/or slopes, divide the run times into three cycles to allow the ground to absorb the water. Additional cycles are created by utilizing more than one start time combined with shorter runtimes.
If you have drip irrigation, follow these guidelines that include how many minutes it takes to water ¼ of an inch:
