What Grows in Kitsap County, Washington

USDA Zones 8b · 253K acres

Kitsap County, in Washington, sits in USDA hardiness zone 8b — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.

Well-matched crops include apple, cherry, hop, and grape, and the gap between "grows in the area" and "grows in your yard" is closed by soil, sun, and drainage.

Kitsap County lies within the Pacific Northwest — a regional growing area with its own character.

Grounded in USDA PHZM 2023 · Growable Ground suitability scoring

Score your parcel · free

Kitsap County holds more than one microclimate.

Soils and elevations shift across Kitsap County, so your frost dates and drainage aren't the county average. 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

8b

Last Frost (state avg.)

Mar 1 - Jun 1

First Frost (state avg.)

Sep 15 - Nov 15

County Area

253K acres

Hardiness Zone Range

8b8b
3a (Cold)13b (Hot)

Growing Season

J
F
M
A
M
J
J
A
S
O
N
D
Last frost: Mar 1 - Jun 1First frost: Sep 15 - Nov 15

Zone maps are averages across Kitsap County. Your yard's slope, trees, and frost pockets shift what actually grows — see your land's exact reading.

Soil in Kitsap County

Across Kitsap County, the ground is predominantly Inceptisols, where Alderwood, Harstine, and Shelton are the most extensive named soil series. The soil is generally moderately well drained with a gravelly ashy sandy loam surface. Topsoil pH runs about 5.3–5.8, strongly acidic. Rainfall drains through hydrologic group B soils.

Soil order

Inceptisols

Drainage

Moderately well drained

Prime farmland

10%

Hydric soils

7%

Soil still varies lot by lot — soil types explained.

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.

Safe to Grow Here?

What the federal record shows across Kitsap County — and how to grow with it.

Federal record: High

We checked the federal record across Kitsap County1,100 documented sites across 7 of the 9 source types we track.

The most significant on record: 18 Superfund sites. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.

Kitsap County carries one of the heavier federal records we track — and that's not a verdict on your yard. Proximity to a documented site is information, not a diagnosis: nothing here says any particular parcel is affected. It does earn one concrete step — before food beds go in the ground, a professional soil test tells you exactly what you're working with, and raised beds with clean imported soil grow well almost anywhere in the meantime.

Sources: EPA, USGS1.8M documented sites tracked nationwide across 9 federal source types.

Environmental Intelligence

Understanding what's nearby helps you make informed decisions about where and how to grow.

Total Sites

1,100

across Kitsap County

Risk Level

High

Highest-severity

18 Superfund sites

Severity Distribution

across Kitsap County

High20Moderate598Low482

Highest-Severity Sites

Bangor Naval Submarine Base
Superfund · Superfund NPL
Bangor Naval Submarine Base
Superfund · Superfund NPL
Bangor/Silverdale Illegal Dump Site
Superfund · Superfund (Non-NPL)
Bremerton City of
PFAS Sampling · PFAS Detected
Camp Wesley Harris Naval Reservation
Superfund · Superfund (Non-NPL)

A note from Gnorman

What an experienced grower watches for around here

In and around Kitsap County, two things run higher than the national average — Nitrate (486 sites) and PFAS (15 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.

Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.

PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.

Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).

Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.

Free Report

Check your specific parcel in Kitsap County

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:

Your soil pHYour frost-free daysYour sun & shade

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

Kitsap County Average

  • USDA Zones 8b
  • 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

Free Report

Read your parcel in Kitsap County

Pull a site-specific report for your exact address in Kitsap County, Washington — soil, sun, drainage, frost risk, and scored plant recommendations.

Three things about your exact spot that zone averages miss:

Your soil pHYour frost-free daysYour sun & shade

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 Kitsap County, Washington

  • USDA Hardiness Zones: 8b (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)
  • County Land Area: 253K acres (US Census TIGER 2025)

Zone data: USDA ARS Plant Hardiness Zone Map 2023. Climate data: NOAA NCEI. County boundaries: US Census TIGER/Line 2025.

Frost dates here are the Kitsap County average. Low spots and tree cover move them by days on any one yard — see your exact frost windows.

Frequently Asked Questions

What hardiness zone is Kitsap County, Washington?

Kitsap County sits in USDA hardiness zone 8b, 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 Kitsap County?

Kitsap County 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 Kitsap County?

Kitsap County's zone 8b supports a wide range — strong performers include Apple, Cherry, Hop, Grape, and Blueberry. 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 Kitsap County, really?

Officially, Kitsap County sits in USDA zone 8b (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 Kitsap County?

The federal record around Kitsap County runs heavier than most — 1,100 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.

Just moved to Kitsap County — what should I know before planting?

Start with three facts. Kitsap County sits in USDA zone 8b, which sets what survives winter; the statewide frost window runs about Mar 1 - Jun 1 to Sep 15 - Nov 15 (NOAA 30-year climate normals); and 1,100 documented sites sit on the federal record here, so a soil test before food beds is the smart first step. From there, matching plants to your actual soil and sun is the fun part.

Everything on this page is a Kitsap County 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.