Grays Harbor 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.
Expect cabbage, fig, california poppy, and collard greens to be strong candidates here; the deciding factors on any one parcel stay local — soil, sun, and drainage.
Grays Harbor County lies within the Olympic Peninsula and the Pacific Northwest — a regional growing area with its own character.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Grays Harbor County holds more than one microclimate.
Soils and elevations shift across Grays Harbor County, so your frost dates and drainage aren't the county average. Enter your address and we'll score 1,086 plants against your land's actual soil, sun, and frost.
We read public map data around Grays Harbor County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Grays Harbor County — the short answer
Grays Harbor County, Washington: USDA zone 8b, about 256 days between hard freezes, across 1.2M acres.
- USDA zone
- 8b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 9
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Nov 20
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~256
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 1.2M acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are county 28°F normals: light frosts run a few weeks past them, and tender transplants usually wait 2–3 weeks after the last hard freeze.
Hardiness Zone Range
Zone 8b is Grays Harbor County's average, not your lot's — a low corner or a tree line moves it. Against Grays Harbor County's 256-day season, see what your own ground reads.
Heat in Grays Harbor County
Across a year, Grays Harbor County accumulates about 1,314 growing degree days above 50°F, about 399 fewer than the middle Washington county — ahead of 11 of Washington’s 39 counties. Degree days are the heat a crop actually gets to work with — more of them is more room to ripen a long-season crop before the freeze closes the window.
Grounded in PRISM Climate Group, Oregon State University — 1991–2020 monthly normals
Soil in Grays Harbor County
Across Grays Harbor County, the ground is predominantly Andisols, where Zenker, Hoquiam, and Mopang are the most extensive named soil series. The soil is generally well drained with a medial silt loam surface. Topsoil pH runs about 4.6–5.3, very strongly acidic. Rainfall drains through hydrologic group B soils.
Soil order
Andisols
Drainage
Well drained
Prime farmland
12%
Hydric soils
6%
Soil still varies lot by lot — soil types explained.
How the ground varies across Grays Harbor County
The USDA soil survey maps 76% of Grays Harbor County as well drained — but another 22% drains differently: 9% moderately well drained, 5% poorly drained.
Zenker is the most extensive named soil at 8% of mapped acres, then Hoquiam (7%) and Mopang (6%).
Which of them your own lot sits on is a parcel question, not a county one. Check your address for the survey at your boundary.
What this means for growing in Grays Harbor County
Each reading below is measured for Grays Harbor County itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Drainage
MeasuredThe dominant soils across Grays Harbor County are well drained, in hydrologic group B — ground that drains quickly.
The upside is soil you can work early in spring and roots that never drown; the cost is that fast-draining ground dries out fast and leaches nutrients away before plants can use them.
Work in compost and mulch to hold moisture and feed, and water more often in short doses than deep and rarely.
USDA NRCS SSURGO
Surface pH
MeasuredTopsoil across Grays Harbor County runs about pH 4.6–5.3, on the acidic side.
Blueberries, potatoes, and rhododendrons thrive in it, but most vegetables start locking out nutrients below about pH 6.0 and grow pale and stunted no matter how much you feed them.
A measured lime application raises pH for the crops that need it — but test first, because the right rate depends on your own soil, not the county average.
USDA NRCS SSURGO
Season length
MeasuredGrays Harbor County runs about 256 days between hard freezes — a long growing season.
There is slack for succession plantings and slow-finishing crops: many vegetables can be sown twice, and the heat-lovers have time to ripen fully.
Plan a second sowing of quick crops after the first comes out, and use the fall window most gardeners let sit idle.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredGrays Harbor County sits in USDA hardiness zone 8b.
The zone sets which perennials, shrubs, and fruit trees live through an average winter here — a plant rated for a colder zone is a safe bet, one rated warmer needs winter protection or gets treated as an annual.
Match perennials and fruit to the zone before you buy, so nothing you plant is a gamble against the cold.
USDA PHZM 2023
The kind of country Grays Harbor County is in
Grays Harbor County sits in the Coast Range — EPA Level III, inside the wider Marine West Coast Forest. One consistent ecological setting across the whole county.
What Grows in Grays Harbor County
We scored all 1,086 plants against Grays Harbor County's own USDA zone 8b and its own 256-day season between hard freezes, using the same matching engine that runs a full parcel report. These cleared both. Sun, soil pH and drainage vary lot by lot — those are the parcel questions below. Each card opens that plant's Washington profile.
Is it too late to plant in Grays Harbor County?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Feb 9; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 9 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 20 — long-season crops need about 90 days of runway, quick greens only 30. With a season this long, “too late” mostly means “switch crops” — second sowings and a full fall garden are the norm, with garlic closing the year.
What gets applied to farmland in Grays Harbor County
USGS estimates 5,451 lb of Glyphosate on Grays Harbor County farmland in 2019, its largest by weight, ahead of Bentazone (1,171 lb) and Metolachlor-s (1,089 lb).
Farmland across the whole county, not any one lot. Check your address for the site-by-site record.
Safe to Grow Here?
What the federal record shows across Grays Harbor County — and how to grow with it.
We checked the federal record across Grays Harbor County — 466 documented sites across 8 of the 9 source types we track.
The most significant on record: 5 Superfund sites (none NPL-listed). Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.
There's a meaningful federal record across Grays Harbor County — worth a look before you plant food, not a reason to hold back from growing. Proximity to a documented site is information, not a diagnosis of any one yard. A soil test before new food beds is the sensible precaution here, and the map shows exactly which sites sit where, so you can see what's actually near you.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
What's on the federal record near Grays Harbor County
Closest first, across Grays Harbor County. Listing isn't leaking, and distance isn't exposure.
- WISHKAH MARKETUnderground Storage Tanks · 0.9 mi
- CENTRAL PARK MAINTENANCEUnderground Storage Tanks · 2.3 mi
- ALFER CREEK MITIGATION SITEUnderground Storage Tanks · 2.5 mi
- UPRR ABERDEENUnderground Storage Tanks · 2.5 mi
- BILL LANE DRILLINGUnderground Storage Tanks · 2.5 mi
- WISHKAH VALLEY SCHOOL DISTRICT 117Underground Storage Tanks · 2.6 mi
- HOQUIAM WATER DEPARTMENTPFAS · 4.5 mi
- JIM W WELLS LOGGING CO INCUnderground Storage Tanks · 5.8 mi
- JOE VALERIO-THREE-WAY SERVICEUnderground Storage Tanks · 5.8 mi
- HOGANS CORNER AIRPORTUnderground Storage Tanks · 5.8 mi
- BUP STATIONUnderground Storage Tanks · 5.8 mi
- OCEAN CITY STATE PARKUnderground Storage Tanks · 5.8 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Grays Harbor County's center, not your beds. Run your own address for what's upwind of you specifically.
Environmental Intelligence
The counts behind that headline — every source type on the record near Grays Harbor County.
Total Sites
466
across Grays Harbor County
Risk Level
Elevated
Highest-severity
5 Superfund sites (none NPL-listed)
Sources Checked
across Grays Harbor County
Severity Distribution
across Grays Harbor County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Grays Harbor County, two things run higher than the national average across Grays Harbor County — PFAS (7 sites) and Underground Storage Tanks (343 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Underground Storage Tanks: Underground storage tanks are the single most common source of soil contamination near homes and gardens.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Use raised beds with imported soil — this eliminates the primary soil-contact pathway.
Check your specific parcel in Grays Harbor County
Get exact proximity distances to contamination sources for your specific parcel — plus soil, sun, drainage, and 1,086 plant recommendations.
25+ data sources read at your address, not the Grays Harbor County average
Your land is one point inside Grays Harbor County
Everything above resolves to Grays Harbor County as a whole — one PHZM band and one county frost record, read across 1.2M acres. Your parcel is one point inside that footprint. Slope, tree cover, a low spot that pools cold air, and what is in the soil are all resolved at the address, and none of them are visible at county scale. That is the honest boundary of this page, and the reason the next step is a reading of your own ground rather than a better county average.
Your Lot vs the Grays Harbor County Average
Grays Harbor County Average
- ●USDA Zones 8b, averaged across Grays Harbor County
- ●One soil character for all of Grays Harbor County
- ●Frost dates read at Grays Harbor County's scale: Mar 9 to Nov 20
YOUR Parcel
- ✓Your exact zone, not Grays Harbor County's 8b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Grays Harbor County
Pull a site-specific report for your exact address in Grays Harbor County, Washington — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Grays Harbor County averages can't show:
We read public map data around Grays Harbor County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Grays Harbor County average
How we know this about Grays Harbor County
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at county grain; hard-freeze dates from NOAA 1991–2020 28°F normals at this county’s own record where one resolves, and the labelled statewide window where none does; soils from the USDA NRCS SSURGO survey, area-weighted across the county’s own map units; boundaries and acreage from US Census TIGER/Line 2025; the contamination and pesticide records from the federal sources named in their beats above. Where Grays Harbor County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Grays Harbor County
When does frost risk typically end in Grays Harbor County?
The last hard freeze (28°F) in Grays Harbor County typically lands around Mar 9, per NOAA 1991–2020 climate normals — earlier than the light-frost dates most charts quote. That marks the hard freeze, not the last light frost — lighter frosts keep biting past it, which is why tender transplants here wait until about Mar 30.
How long is the growing season in Grays Harbor County?
Measured between 28°F hard freezes, Grays Harbor County sees about 256 frost-free days — roughly Mar 9 through Nov 20, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Mar 30 to Nov 6, about 221 days.
Is the soil safe to grow vegetables in Grays Harbor County?
The federal record around Grays Harbor County is a meaningful one — 466 documented sites, mostly Underground Storage Tanks entries (343), the nearest Underground Storage Tanks record about 0.9 miles out — so a soil test before new food beds is a sensible precaution here, not a reason to hold back from growing. Remember that proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what sits where.
Everything above is measured at Grays Harbor County's scale — its 8b band and its 256-day season. Your yard writes its own version of Grays Harbor County's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
Will It Grow Here?
Zone fit is the first question — each answer below reads Washington's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at Grays Harbor County’s own scale
8 of the readings below were taken at Grays Harbor County's own scale — its own ~256-day span between 28°F freezes, the 3 most extensive soil series mapped here and 466 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Grays Harbor County's own USDA hardiness band, zones 8bUSDA PHZM 2023
- Grays Harbor County's own 28°F hard-freeze dates and its ~256-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Grays Harbor CountyUSDA NRCS SSURGO
- 466 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Underground Storage Tanks record about 0.9 miles outFederal environmental registers
- Grays Harbor County's boundary and the 1,217,450 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 8b and a ~256-day seasonGrowable Ground crop-matching engine
- Grays Harbor County sitting wholly inside the Coast RangeUS EPA Level III Ecoregions
- Which agricultural compounds go onto Grays Harbor County farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every Washington grower plans around — written at state scale, so they stay on the state guidefrom Washington
What this page can’t tell you
- How the season shifts across Grays Harbor County — the ~256 days above is one reading at its centre; the 12 towns below each carry their owntowns in this county →
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Grays Harbor County's 1,217,450 acreswhy one lot differs from the next →
- Which of those 466 documented sites actually reaches your soil — that needs your address, the wind, and the groundwater directionhow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — none of it survives being averaged over Grays Harbor Countyread your own land →