Sedro-Woolley, Washington, sits in USDA hardiness zone 8b — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
Among the crops suited to this profile: cabbage, fig, california poppy, and collard greens. The site-level story — soil, sun, drainage — decides the rest.
Even in Sedro-Woolley, 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 Sedro-Woolley 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 Sedro-Woolley — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Sedro-Woolley — the short answer
Sedro-Woolley, Washington: USDA zone 8b, about 277 days between hard freezes, across 3K acres of city.
- USDA zone
- 8b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Feb 21
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 25
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~277
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 3K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are this town’s own 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 Sedro-Woolley's average, not your lot's — a low corner or a tree line moves it. Against Sedro-Woolley's 277-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Sedro-Woolley
Each reading below is measured for Sedro-Woolley itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredSedro-Woolley runs about 277 days between hard freezes — 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
MeasuredSedro-Woolley 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 Sedro-Woolley is in
Sedro-Woolley sits in the Puget Lowland — EPA Level III, inside the wider Marine West Coast Forest. That is read at Sedro-Woolley's own centroid, and it is not what its county reads: Skagit County is mostly North Cascades. The wider page above you is answering a different question about different ground.
What Grows in Sedro-Woolley
Every plant below cleared Sedro-Woolley's own zone 8b and its 277-day season. Each card opens that plant's Washington profile. How we score.
Is it too late to plant in Sedro-Woolley?
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 24; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Feb 21 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 25 — 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 Sedro-Woolley
Closest first, within ~10 miles of Sedro-Woolley. Listing isn't leaking, and distance isn't exposure.
- JANICKI LOGGING CO INCUnderground Storage Tanks · 1100 ft
- NORTH CASCADES NATIONAL PARK HEADQUARTERSToxics Release Inventory · 1300 ft
- CONSUMER RENTAL CENTER INCUnderground Storage Tanks · 1300 ft
- SEDRO WOOLEY AM/PMUnderground Storage Tanks · 1300 ft
- RAYS MOBILUnderground Storage Tanks · 1700 ft
- SKAGIT MANUFACTURING CO/DELTA RESOURCEUnderground Storage Tanks · 2100 ft
- JANICKI INDUSTRIES INC SEDRO WOOLLEYBrownfields · 2200 ft
- JANICKI INDUSTRIES INC SEDRO WOOLLEYToxics Release Inventory · 2200 ft
- SKAGIT MANUFACTURING SITEToxics Release Inventory · 2300 ft
- WOOLLEYSUnderground Storage Tanks · 2500 ft
- CHEVRON 97502Underground Storage Tanks · 0.5 mi
- SEDRO WOOLLEY CENTRAL OFFICEUnderground Storage Tanks · 0.5 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Sedro-Woolley'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 Sedro-Woolley.
Total Sites
389
within ~10 miles of Sedro-Woolley
Risk Level
Elevated
Highest-severity
15 Toxics Release Inventory facilities
Sources Checked
within ~10 miles of Sedro-Woolley
Severity Distribution
within ~10 miles of Sedro-Woolley
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Sedro-Woolley, two things run higher than the national average within ~10 miles of Sedro-Woolley — CAFO (26 sites) and Underground Storage Tanks (252 sites). That's not a problem with your land — it's information about it.
CAFO: CAFOs pose a different contamination profile than chemical sources.
Underground Storage Tanks: Underground storage tanks are the single most common source of soil contamination near homes and gardens.
Wash all produce consumed raw thoroughly, especially leafy greens grown near CAFOs.
Use raised beds with imported soil — this eliminates the primary soil-contact pathway.
Check your specific parcel in Sedro-Woolley
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 Sedro-Woolley average
Your land is one point inside Sedro-Woolley
Everything above resolves to Sedro-Woolley as a whole — one PHZM band and one 28°F frost record, read across 3K 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 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 Sedro-Woolley Average
Sedro-Woolley Average
- ●USDA Zones 8b, averaged across Sedro-Woolley
- ●One soil character for all of Sedro-Woolley
- ●Frost dates read at Sedro-Woolley's scale: Feb 21 to Nov 25
YOUR Parcel
- ✓Your exact zone, not Sedro-Woolley's 8b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Sedro-Woolley
Pull a site-specific report for your exact address in Sedro-Woolley, Washington — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Sedro-Woolley averages can't show:
We read public map data around Sedro-Woolley — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Sedro-Woolley average
How we know this about Sedro-Woolley
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 Sedro-Woolley’s own record; 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 Sedro-Woolley
When does frost risk typically end in Sedro-Woolley?
The last hard freeze (28°F) in Sedro-Woolley typically lands around Feb 21, 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 14.
When is the first frost in Sedro-Woolley?
The first hard freeze (28°F) in Sedro-Woolley typically arrives around Nov 25, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 11, so the watching starts about Oct 26 — about 277 days after the spring freeze cleared.
How long is the growing season in Sedro-Woolley?
Measured between 28°F hard freezes, Sedro-Woolley sees about 277 frost-free days — roughly Feb 21 through Nov 25, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Mar 14 to Nov 11, about 242 days.
Is the soil safe to grow vegetables in Sedro-Woolley?
The federal record around Sedro-Woolley is a meaningful one — 389 documented sites, mostly Underground Storage Tanks entries (252), the nearest Underground Storage Tanks record about 0.2 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 Sedro-Woolley?
From about Oct 26 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 25 (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 25. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Sedro-Woolley's scale — its 8b band and its 277-day season. Your yard writes its own version of Sedro-Woolley'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 Sedro-Woolley’s own scale
6 of the readings below were taken at Sedro-Woolley's own scale — its own ~277-day season between 28°F freezes, the 2,782 acres it covers and 389 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Sedro-Woolley's own USDA hardiness band, zones 8bUSDA PHZM 2023
- Sedro-Woolley's own 28°F hard-freeze dates, about Feb 21 and Nov 25 and the ~277-day span between themNOAA 1991–2020 Climate Normals
- 389 documented contamination sites on the federal record near Sedro-Woolley, the closest Underground Storage Tanks record about 0.2 miles out from the town centreFederal environmental registers
- Sedro-Woolley's boundary and the 2,782 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 8b and a ~277-day seasonGrowable Ground crop-matching engine
- Sedro-Woolley sits in the Puget Lowland — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Sedro-Woolley's 2,782 acres read through its county's SSURGO summaryfrom Skagit County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Skagit 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 Skagit County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Sedro-Woolley's 2,782 acreswhy one lot differs from the next →
- Which side of Sedro-Woolley you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 2,782 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.2 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 Sedro-Woolley-wide figureread your own land →