Perennial

When to Plant Hostas in Washington

The king of shade gardens. Hostas come in hundreds of varieties and get more beautiful with each passing year.

The Short Answer

Western Washington grows excellent hostas — the cool, moist maritime climate is ideal for shade plants. The Puget Sound region's many mature conifers and deciduous trees provide perfect dappled shade conditions. Eastern Washington is too hot and dry for hostas without significant shade and irrigation.

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

Hostas 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

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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 Hostas in Washington

State-Specific Growing Tips

Western WA: plant from March through September. The cool, moist maritime climate is hosta heaven — the plants rarely face heat stress. Slugs are the tradeoff. Eastern WA: only in deep shade with consistent irrigation — conditions difficult to maintain in the dry climate. WSU Extension includes hostas in shade garden recommendations for western Washington.

Recommended Varieties for Washington

Western WA: the full range thrives. The cool climate accommodates even thin-leaved varieties that struggle in hot climates. Eastern WA: heat-tolerant types only, if attempting.

Common Challenges in Washington

Slugs in western WA — the #1 challenge. Iron phosphate bait is essential. Deer in suburban areas. In eastern WA, heat and drought make hostas impractical for most gardens.

Growing Tips

Plant divisions or nursery plants in spring or fall. Slugs are the main enemy — use iron phosphate bait. Mulch to retain moisture.

Companion Planting

Plant hostas alongside these companions for better growth:

Ferns Astilbe Heuchera

The Bottom Line

Hostas 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

Hostas Growing Guide National planting guide with all states Washington Planting Calendar All plants for Washington Hostas in Alabama Alabama planting dates Hostas in Alaska Alaska planting dates Hostas in Arizona Arizona planting dates Hostas 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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