Perennial Flower

When to Plant Daylilies in Washington

Nearly indestructible perennials with stunning trumpet-shaped blooms. Each flower lasts just one day, but the show goes on for weeks.

The Short Answer

Daylilies grow well in Washington, with the cool western climate supporting long bloom periods and the hot eastern climate producing vigorous growth.

Washington Frost Dates

Your planting dates depend on which part of Washington you're in. Here are the frost date ranges by region:

Region Zones Last Frost (Spring) First Frost (Fall)
Western Washington (Seattle/Tacoma) 8a, 8b Mar 25 - Apr 15 Oct 25 - Nov 15
Puget Sound 8b, 9a Mar 15 - Apr 5 Nov 1 - Nov 20
Eastern Washington 5b, 6a, 6b, 7a Apr 25 - May 15 Sep 25 - Oct 15
Central Washington 6a, 6b, 7a Apr 20 - May 10 Oct 1 - Oct 20

Daylilies Planting Schedule for Washington

Western Washington (Seattle/Tacoma) (Zones 8a, 8b)

Average last frost: Mar 25 - Apr 15 · Average first frost: Oct 25 - Nov 15

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0 wks after frost

Puget Sound (Zones 8b, 9a)

Average last frost: Mar 15 - Apr 5 · Average first frost: Nov 1 - Nov 20

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0 wks after frost

Eastern Washington (Zones 5b, 6a, 6b, 7a)

Average last frost: Apr 25 - May 15 · Average first frost: Sep 25 - Oct 15

Transplant Outside
0 wks after frost

Central Washington (Zones 6a, 6b, 7a)

Average last frost: Apr 20 - May 10 · Average first frost: Oct 1 - Oct 20

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0 wks after frost

Growing Daylilies in Washington

State-Specific Growing Tips

Plant from March through September. Full sun to partial shade. Daylilies are one of the more reliable perennials for western Washington — they handle the cool, moist climate better than many sun-loving plants. Eastern WA: full sun, irrigation.

Recommended Varieties for Washington

Dormant types for eastern WA's cold winters. Semi-evergreen for western WA's mild conditions. Stella de Oro and Happy Returns for universal reliability.

Common Challenges in Washington

Slugs in western WA. Deer browse. Otherwise trouble-free in both regions.

Growing Tips

Plant bare-root or divisions in spring or fall. Divide clumps every 3-4 years to maintain vigor. Deadhead to keep gardens tidy.

Companion Planting

Plant daylilies alongside these companions for better growth:

Coneflowers Black Eyed Susans

The Bottom Line

Daylilies can be grown successfully in Washington with proper attention to regional frost dates and local growing conditions. Timing varies across the state — Western Washington (Seattle/Tacoma) gardeners work with a last frost around Mar 25 - Apr 15, while Central Washington sees frost end around Apr 20 - May 10. Choose varieties suited to your region, amend your soil based on its specific needs, and monitor for the pests and diseases most common in your area. For exact dates based on your zip code, use our free planting date finder.

Related Guides

Daylilies Growing Guide National planting guide with all states Washington Planting Calendar All plants for Washington Daylilies in Alabama Alabama planting dates Daylilies in Alaska Alaska planting dates Daylilies in Arizona Arizona planting dates Daylilies in Arkansas Arkansas planting dates
Note: All dates are based on NOAA 30-year Climate Normals and represent historical averages, not predictions for any specific year. Always check your local weather forecast before planting frost-sensitive crops. Learn about our data sources.

Last reviewed: March 29, 2026

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