Oak Harbor, 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.
The conditions favor cabbage, fig, california poppy, and collard greens, among others — though every individual site edits that list with its own soil, sun, and drainage.
Even in Oak Harbor, 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 Oak Harbor lot. 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 Oak Harbor — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Oak Harbor — the short answer
Oak Harbor, Washington: USDA zone 8b, about 292 days between hard freezes, across 6K acres of city.
- USDA zone
- 8b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Feb 8
- Island County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Nov 27
- Island County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~292
- Island County normal — NOAA 1991–2020, nearest to this town
- City area
- 6K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. No 30-year normal resolves at this town’s own centroid, so the hard-freeze dates are Island County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 8b is Oak Harbor's average, not your lot's — a low corner or a tree line moves it. Against Oak Harbor's 292-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Oak Harbor
Each reading below is measured for Oak Harbor itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsOak Harbor runs about 292 days between hard freezes (read from Island County, the closest normal to Oak Harbor) — close to year-round growing.
Frost is rarely the limit here; winter plantings are as real as summer ones, and the harder question is which crops shrug off the summer heat.
Grow cool-season crops through the mild winter, and choose heat-tolerant varieties for the summer beds.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredOak Harbor 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 Oak Harbor is in
Oak Harbor sits in the Puget Lowland — EPA Level III, inside the wider Marine West Coast Forest. That is read at Oak Harbor's own centroid rather than borrowed from Island County.
What Grows in Oak Harbor
Every plant below cleared Oak Harbor's own zone 8b and its 292-day season. Each card opens that plant's Washington profile. How we score.
Is it too late to plant in Oak Harbor?
For most of the year, no — what changes is which crops still fit the days remaining. Cool-season crops can go in from around Jan 11; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Feb 8 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 27 — long-season crops need about 90 days of runway, quick greens only 30. And with a calendar this mild, the honest answer is that planting barely stops — winter opens seasons colder regions never see.
What's on the federal record near Oak Harbor
Closest first, within ~10 miles of Oak Harbor. Listing isn't leaking, and distance isn't exposure.
- OAK HARBOR ROAD SHOPUnderground Storage Tanks · 2600 ft
- OAK HARBOR MARINAUnderground Storage Tanks · 0.5 mi
- US NAVY AIR STATION WHIDBEY ISLAND SPBBrownfields · 0.6 mi
- OAK HARBOR SCHOOL DISTRICTUnderground Storage Tanks · 0.7 mi
- HILLTOP TEXACOUnderground Storage Tanks · 0.7 mi
- OIL WELLUnderground Storage Tanks · 0.8 mi
- CHEVRON MIDWAY OAK HARBORUnderground Storage Tanks · 0.8 mi
- NAVAL AIR STATION, WHIDBEY ISLAND (SEAPLANE BASE)Superfund · 0.8 mi
- OAK HARBOR FIRE DEPARTMENTBrownfields · 0.9 mi
- TESORO 62155Underground Storage Tanks · 1.0 mi
- MIDWAY SHELL SERVICEUnderground Storage Tanks · 1.1 mi
- SOUTHLAND CORP 2306-18255AUnderground Storage Tanks · 1.1 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Oak Harbor'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 Oak Harbor.
Sources Checked
within ~10 miles of Oak Harbor
Severity Distribution
within ~10 miles of Oak Harbor
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Oak Harbor, two things run higher than the national average within ~10 miles of Oak Harbor — PFAS (7 sites) and Superfund (4 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.
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 Oak Harbor
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 Oak Harbor average
Your land is one point inside Oak Harbor
Everything above resolves to Oak Harbor as a whole — one PHZM band, read across 6K acres, with hard-freeze dates borrowed from Island County’s record because no 30-year normal resolves at this city’s own centroid. 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 city 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 local average.
Your Lot vs the Oak Harbor Average
Oak Harbor Average
- ●USDA Zones 8b, averaged across Oak Harbor
- ●One soil character for all of Oak Harbor
- ●Frost dates read at Oak Harbor's scale: Feb 8 to Nov 27
YOUR Parcel
- ✓Your exact zone, not Oak Harbor's 8b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Oak Harbor
Pull a site-specific report for your exact address in Oak Harbor, Washington — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Oak Harbor averages can't show:
We read public map data around Oak Harbor — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Oak Harbor average
How we know this about Oak Harbor
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this city’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Island County’s record, because none resolves here; boundaries and acreage from US Census TIGER/Line 2025; the contamination records from the federal sources named in their beats above. Soil is not read at city grain anywhere on this page — there is no city-resolution survey in our data, which is why you will find no soil grid here rather than a statewide one wearing a local label. The resolution ledger below names every figure this page inherited.
Common questions about Oak Harbor
When does frost risk typically end in Oak Harbor?
The last hard freeze (28°F) in Oak Harbor typically lands around Feb 8, 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 1.
When is the first frost in Oak Harbor?
The first hard freeze (28°F) in Oak Harbor typically arrives around Nov 27, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 13, so the watching starts about Oct 28 — about 292 days after the spring freeze cleared.
How long is the growing season in Oak Harbor?
Measured between 28°F hard freezes, Oak Harbor sees about 292 frost-free days — roughly Feb 8 through Nov 27, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Mar 1 to Nov 13, about 257 days.
Is the soil safe to grow vegetables in Oak Harbor?
The federal record around Oak Harbor is a meaningful one — 169 documented sites, mostly Underground Storage Tanks entries (83), the nearest Underground Storage Tanks record about 0.5 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.
How do I protect my plants from frost in Oak Harbor?
From about Oct 28 the job here turns from planting to protecting — the last start even a 30-day crop can finish. As the season closes around the first 28°F hard freeze near Nov 27 (NOAA 1991–2020 climate normals), three moves buy time: row cover or an old sheet over tender plants on still, clear nights; water the soil the afternoon before a freeze, so it holds warmth overnight; and harvest tomatoes, peppers and basil before Nov 27. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Oak Harbor's scale — its 8b band and its 292-day season. Your yard writes its own version of Oak Harbor's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
What this page reads at Oak Harbor’s own scale
5 of the readings below were taken at Oak Harbor's own scale — the 6,184 acres it covers and 169 documented sites around it; 5 are borrowed from a wider read, named and linked below.
Measured here
- Oak Harbor's own USDA hardiness band, zones 8bUSDA PHZM 2023
- 169 documented contamination sites on the federal record near Oak Harbor, the closest Underground Storage Tanks record about 0.5 miles out from the town centreFederal environmental registers
- Oak Harbor's boundary and the 6,184 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 8b and a ~292-day seasonGrowable Ground crop-matching engine
- The ecoregion at Oak Harbor's own centroid, the Puget LowlandUS EPA Level III Ecoregions
Inherited from a wider read
- The 28°F hard-freeze dates — Oak Harbor has no normal of its own, so its county's is the closest measured readfrom Island County
- Soil character — no town-scale survey exists, so Oak Harbor's 6,184 acres read through its county's SSURGO summaryfrom Island County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Island County
- The growing challenges every Washington grower plans around — written at state scale, so they stay on the state guidefrom Washington
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Island County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Oak Harbor's 6,184 acreswhy one lot differs from the next →
- Which side of Oak Harbor you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 6,184 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.5 miles out, measured from the town centrehow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — measured at your address, and averaged away by any Oak Harbor-wide figureread your own land →