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, October 30, 2026
Conditions: Nighttime temperatures are cooler and daylight hours are shorter.
Watering recommendation:
- Stop watering established plants for the season.
We’ll see you in March!
This is the last Weekly Watering Advice you’ll receive from me for the 2026 season. Please take this 60-second survey to tell me about your experience!
It’s been a great gardening season! I’ve shared many tips to help you use water efficiently in your landscape and garden – from building healthy soil to choosing the right plants, to using mulch and optimizing your sprinkler system. It was a lot to cover!
My last tip: Don’t water between November and April. If you choose to water during any of these months, it may contribute to a higher sewer bill.
If you have questions about plants, soils, sprinkler systems, or anything else related to wise water use in your landscape, please don’t hesitate to reach out to me at Mark.Guthrie@seattle.gov. Otherwise, we’ll see you again in March!
Resources
- Learn more about seasonal gardening practices
- 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 |
 | High-efficiency Spray Nozzles | 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:
