USDA hardiness zones — 2023 map
Washington hardiness zones — USDA planting zone map + what to grow
Zones 4a-9a · most of Washington is zone 8a · Pacific region
WashingtonUSDA zone range & map
On the 2023 USDA Plant Hardiness Zone Map, Washington spans zones 4a-9a. The map shades the state from the Cascades and northeast highlands (zone 4a) through to the Puget Sound lowland around Seattle (zone 9a). The single most common half-zone across the populated state is zone 8a — that is the figure to use if you only remember one number for Washington. Washington is split by the Cascades into a mild, wet, long-season west and a colder, drier east. The Puget Sound lowland is the mildest belt.
| USDA zone range | Zones 4a-9a |
|---|---|
| Most common zone | Zone 8a |
| Coldest area | the Cascades and northeast highlands (zone 4a) |
| Warmest area | the Puget Sound lowland around Seattle (zone 9a) |
| Average last spring frost | mid-April (Puget Sound) |
| Average first fall frost | early November (Puget Sound) |
Source: USDA 2023 Plant Hardiness Zone Map (1991-2020 normals). Frost averages: NOAA/NCEI 1991-2020 climate normals. Local ZIP-level zones and frost dates can differ from these statewide figures.
Washington hardiness zones by major city
Zones shift across Washington with elevation and distance from the coast. Here is the 2023 USDA half-zone for the largest cities:
| City | USDA zone |
|---|---|
| Seattle | Zone 9a |
| Spokane | Zone 7a |
| Tacoma | Zone 8b |
| Vancouver | Zone 8b |
| Yakima | Zone 7a |
Need your exact zone? Run the ZIP-code zone finder for a precise half-zone and frost dates for your address.
ZIP-code zones in Washington
Statewide ranges hide a lot. Tap your area for its exact USDA half-zone, last and first frost dates, and what to plant now:
- Federal Way 98003 — Zone 8b
- Bellevue (Crossroads) 98007 — Zone 8b
- Bothell 98012 — Zone 8b
- Kent 98030 — Zone 8b
- Kent (West) 98032 — Zone 8b
- Kirkland 98034 — Zone 8b
- Redmond 98052 — Zone 8b
- Renton 98055 — Zone 8b
- Renton (Highlands) 98056 — Zone 8b
- Seattle 98101 — Zone 9a
- Seattle (Fremont) 98103 — Zone 8b
- Seattle (University District) 98105 — Zone 9a
- Seattle (Queen Anne) 98109 — Zone 9a
- Seattle (Wedgwood) 98115 — Zone 9a
- Seattle (Columbia City) 98118 — Zone 9a
- Seattle (Lake City) 98125 — Zone 8b
- Seattle (Bitter Lake) 98133 — Zone 8b
- SeaTac 98198 — Zone 8b
- Everett 98201 — Zone 8b
- Bellingham 98225 — Zone 8b
- Marysville 98270 — Zone 8b
- Poulsbo 98370 — Zone 8b
- Puyallup 98372 — Zone 8b
- Tacoma 98401 — Zone 8b
- Olympia 98501 — Zone 8b
- Vancouver 98660 — Zone 8b
- Wenatchee 98801 — Zone 6b
- Moses Lake 98837 — Zone 6b
- Yakima 98902 — Zone 6b
- Ellensburg 98926 — Zone 6b
- Spokane 99201 — Zone 7a
- Spokane (North) 99205 — Zone 6b
- Pasco 99301 — Zone 7a
- Kennewick 99336 — Zone 7a
- Richland 99354 — Zone 7a
What Washington's zone range means for planting
Your hardiness zone tells you which perennials, shrubs, and trees will survive a typical Washington winter, and it anchors when tender crops can go outside. Because Washington spans 4a-9a, two gardeners in the same state can have very different planting calendars.
- Pick perennials hardy to your local zone. Across most of Washington that means at least zone 8a; gardeners in the Cascades and northeast highlands (zone 4a) should choose hardier plants.
- Anchor tender crops to your frost dates. With a last spring frost around mid-April (Puget Sound) and first fall frost around early November (Puget Sound), set out tomatoes, peppers, and basil after the last frost and protect them before the first.
- Adjust for your microclimate. Urban heat, a south-facing slope, or a cold valley pocket can shift your effective zone and frost dates by a half-zone or more from the statewide figure.
Find your exact zone in Washington
The 4a-9a range is statewide. Growli pins your hardiness zone and frost dates to your exact ZIP code and sends a push notification before any forecast frost night for your saved location.
Frequently asked questions
What hardiness zone is Washington?
Washington spans USDA hardiness zones 4a-9a on the 2023 USDA Plant Hardiness Zone Map. The most common zone — covering the largest share of the populated state — is zone 8a. The coldest areas are the Cascades and northeast highlands (zone 4a) and the warmest are the Puget Sound lowland around Seattle (zone 9a).
When is the last frost in Washington?
Across most of Washington the average last spring frost falls around mid-April (Puget Sound) and the first fall frost around early November (Puget Sound). These are statewide averages — colder, higher areas run later in spring and earlier in fall, so check a ZIP-level estimate for your exact spot.
What grows well in Washington?
Washington is split by the Cascades into a mild, wet, long-season west and a colder, drier east. The Puget Sound lowland is the mildest belt. Match plants to your local half-zone within the 4a-9a range: choose varieties hardy to at least zone 8a for reliable overwintering, and time tender crops around your local frost dates. The zone 8 planting guide lists vegetables, fruit, and ornamentals suited to most of the state.
Why does Washington have more than one hardiness zone?
Hardiness zones track the average annual coldest temperature, which changes with latitude, elevation, distance from water, and urban heat. That is why Washington ranges from the Cascades and northeast highlands (zone 4a) to the Puget Sound lowland around Seattle (zone 9a) — a span of 4a-9a — even though it is a single state.
Did Washington's hardiness zone change in 2023?
The USDA updated the Plant Hardiness Zone Map in November 2023 using 1991-2020 climate data. About half the country, including parts of Washington, shifted to the next warmer half-zone versus the 2012 map. The 4a-9a range here reflects the current 2023 map. Always confirm your address against the official USDA map for plant-survival decisions.