Coupeville, Washington, sits in USDA hardiness zones 3a-4b — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
Reliable performers under these conditions include apple, cherry, hop, and blueberry; what your own ground favors still comes down to its soil, sun, and drainage.
Even in Coupeville, no two yards are alike.
A low spot, a south-facing slope, or a stand of trees moves the frost date and sun across a single Coupeville lot. Enter your address and we'll score 1,112 plants against your land's actual soil, sun, and frost.
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Quick Facts
USDA Zones
3a-4b
Last Frost (state avg.)
Mar 1 - Jun 1
First Frost (state avg.)
Sep 15 - Nov 15
Town Area
813 acres
Hardiness Zone Range
Growing Season
Zone maps are averages across Coupeville. Your yard's slope, trees, and frost pockets shift what actually grows — see your land's exact reading.
Soil varies lot by lot — soil types explained.
What Grows in Coupeville
Plants matched to Coupeville's USDA zones 3a-4b — each links to its full growing profile.












Growing Challenges in Washington
What an experienced grower plans around here — each one has a move.

Extreme rain divide: 90+ inches west, 6 inches east of Cascades
Plant to your side of the Cascades, not to the state — your exact spot's rainfall decides the whole plan.

East side requires irrigation — no rain from June through September
With no summer rain, drip lines and deep mulch are the growing season — set them up before June.

Slug and root rot pressure on the wet west side
Raise the beds, bait the slugs, and water mornings only — the wet-side trio that keeps roots and leaves healthy; extension has the details.

Short seasons at elevation in the Cascades and northeast corners
In the short-season corners, fast varieties plus a cold frame or tunnel reliably close the gap.
For cultivar selection, pest pressure, and planting-time guidance specific to Washington, the WSU Extension is the authoritative local source.
Environmental Intelligence
Understanding what's nearby helps you make informed decisions about where and how to grow.
Sources Checked
within ~10 miles of Coupeville
Severity Distribution
within ~10 miles of Coupeville
Highest-Severity Sites

A note from Gnorman
What an experienced grower watches for around here
In and around Coupeville, two things run higher than the national average — PFAS (6 sites) and Superfund (5 sites). It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Superfund: Superfund sites represent the most severe contamination in the federal system.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).
Check your specific parcel in Coupeville
Get exact proximity distances to contamination sources for your specific parcel — plus soil, sun, drainage, and 1,112 plant recommendations.
Three things about your exact spot that zone averages miss:
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources analyzed in seconds
Your Specific Parcel Matters
Coupeville Average
- ●USDA Zones 3a-4b
- ●Generic soil type for the area
- ●State-average frost dates
YOUR Parcel
- ✓Your exact hardiness zone
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Coupeville
Pull a site-specific report for your exact address in Coupeville, Washington — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your exact spot that zone averages miss:
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources analyzed in seconds
Key Growing Facts for Coupeville, Washington
- USDA Hardiness Zones: 3a-4b (USDA PHZM 2023)
- Last Spring Frost (state avg.): Mar 1 - Jun 1 (NOAA 30-Year Climate Normals)
- First Fall Frost (state avg.): Sep 15 - Nov 15 (NOAA 30-Year Climate Normals)
- Land Area: 813 acres (US Census TIGER 2025)
Zone data: USDA ARS Plant Hardiness Zone Map 2023. Climate data: NOAA NCEI. Boundaries: US Census TIGER/Line 2025.
Frequently Asked Questions
What hardiness zone is Coupeville, Washington?
Coupeville sits in USDA hardiness zones 3a-4b, per the USDA Plant Hardiness Zone Map 2023. Zones reflect average annual extreme minimum temperatures from 1991–2020 weather data.
When does frost risk typically end in Coupeville?
Coupeville follows Washington's statewide frost window: last spring frost around Mar 1 - Jun 1 and first fall frost around Sep 15 - Nov 15, per NOAA 30-year climate normals (1991–2020). Frost dates shift with elevation and local microclimate, so watch your own site's cold pockets.
What vegetables grow in Coupeville?
Coupeville's zones 3a-4b support a wide range — strong performers include Apple, Cherry, Hop, Blueberry, and Raspberry. What actually takes on any one site comes down to its soil, sun, and drainage, and we score each plant against the real conditions at your address.
Which hardiness zone is Coupeville, really?
Officially, Coupeville sits in USDA zones 3a-4b (USDA PHZM 2023) — but a zone is a 30-year average of winter's coldest night across an area, and it can't see any one yard. A south-facing slope, a tree line, or a low frost pocket can shift a single site by half a zone either way, which is why neighboring gardeners often quote different numbers. We read the conditions at your exact address — soil, sun, slope, and frost — and score 1,112 plants against what's actually there.
Is the soil safe to grow vegetables in Coupeville?
The federal record around Coupeville runs heavier than most — 168 documented sites — so test the soil before planting food in the ground, and raised beds with clean imported soil grow well in the meantime. Even here, proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what's recorded and where.
How do I protect my plants from frost in Coupeville?
As the season closes around Washington's first fall frost near Sep 15 - Nov 15 (NOAA 30-year climate normals (1991–2020)), a few moves buy time: cover tender plants with floating row cover or an old sheet on still, clear nights, water the soil the afternoon before a freeze so it holds warmth overnight, and harvest frost-tender crops like tomatoes, peppers, and basil before the first hard night. Hardy greens and root crops shrug off light frost and often sweeten after it, so leave them in.
Everything on this page is a Coupeville average. Your yard writes its own version — we read soil, sun, drainage, and frost at your exact address. Try it for 14 days — no card required.
