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: Thursday, July 2, 2026
Conditions: We’ve had mild weather, which may continue into next week.
Watering recommendation:
- Established high-water-use plants: If the soil is dry beneath the surface, water ½ inch once this week.
- Established deep-rooted plants with deep mulch over the soil: There is no need to water this week.
Save water with drip irrigation!
A well-designed drip irrigation system is the most efficient way to water plants. When plants are spaced far apart, add one or two emitters at each plant. For closely spaced plants, install drip irrigation like a grid (as shown in the photo) to get the roots wet.
Keep in mind that drip irrigation systems apply water very slowly. This means you may need to run them longer, especially in clay soils. Visit your drip irrigation manufacturer’s website for tips on system design and installation or view the drip irrigation resources below.
Warm weather has arrived! Have specific questions about drip irrigation? Reach out to Mark.Guthrie@seattle.gov.
Resources
- Learn more about drip irrigation and soaker hoses
- 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:
