Sultan, Washington, sits in USDA hardiness zone 8b — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
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 Sultan, 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 Sultan 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 Sultan — soil, climate, flood, and parcel records. How we handle your address.
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Sultan — the short answer
Sultan, Washington: USDA zone 8b, about 267 days between hard freezes, across 2K acres of city.
- USDA zone
- 8b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Feb 28
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 22
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~267
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 2K 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 Sultan's average, not your lot's — a low corner or a tree line moves it. Against Sultan's 267-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Sultan
Each reading below is measured for Sultan itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredSultan runs about 267 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
MeasuredSultan 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 Sultan is in
Sultan sits in the Puget Lowland — EPA Level III, inside the wider Marine West Coast Forest. That is read at Sultan's own centroid, and it is not what its county reads: Snohomish County is mostly North Cascades. The wider page above you is answering a different question about different ground.
What Grows in Sultan
Every plant below cleared Sultan's own zone 8b and its 267-day season. Each card opens that plant's Washington profile. How we score.
Is it too late to plant in Sultan?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Jan 31; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Feb 28 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 22 — long-season crops need about 90 days of runway, quick greens only 30. Here the calendar nearly circles: cool-season crops take the winter shift, and the next window is always close.
What's on the federal record near Sultan
Closest first, within ~10 miles of Sultan. Listing isn't leaking, and distance isn't exposure.
- AMOUR FIBERSuperfund · 0.5 mi
- JAMES B WILCOX FORD CEDAR PRODUCTS INCUnderground Storage Tanks · 0.6 mi
- A J CLONINGER JRUnderground Storage Tanks · 0.6 mi
- ROMAC INDUSTRIES INCUnderground Storage Tanks · 0.6 mi
- Sultan TexacoUnderground Storage Tanks · 0.6 mi
- ROMAC INDUSTRIESBrownfields · 0.6 mi
- ROMAC INDUSTRIESToxics Release Inventory · 0.6 mi
- SNOHOMISH COUNTYUnderground Storage Tanks · 0.6 mi
- SULTAN CENTRAL OFFICE 2180-B02Underground Storage Tanks · 0.7 mi
- HOOT OWL CHEVRONUnderground Storage Tanks · 0.7 mi
- MIDDLE SCHOOL SITEUnderground Storage Tanks · 0.8 mi
- SKY VALLEY AUTOMOTIVE INCUnderground Storage Tanks · 0.8 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Sultan'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 Sultan.
Total Sites
260
within ~10 miles of Sultan
Risk Level
Elevated
Highest-severity
2 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Sultan
Severity Distribution
within ~10 miles of Sultan
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Sultan, two things run higher than the national average within ~10 miles of Sultan — PFAS (6 sites) and Nitrate (118 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.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in Sultan
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 Sultan average
Your land is one point inside Sultan
Everything above resolves to Sultan as a whole — one PHZM band and one 28°F frost record, read across 2K 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 Sultan Average
Sultan Average
- ●USDA Zones 8b, averaged across Sultan
- ●One soil character for all of Sultan
- ●Frost dates read at Sultan's scale: Feb 28 to Nov 22
YOUR Parcel
- ✓Your exact zone, not Sultan's 8b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Sultan
Pull a site-specific report for your exact address in Sultan, Washington — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Sultan averages can't show:
We read public map data around Sultan — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Sultan average
How we know this about Sultan
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 Sultan’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 Sultan
When does frost risk typically end in Sultan?
The last hard freeze (28°F) in Sultan typically lands around Feb 28, 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 21.
When is the first frost in Sultan?
The first hard freeze (28°F) in Sultan typically arrives around Nov 22, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 8, so the watching starts about Oct 23 — about 267 days after the spring freeze cleared.
How long is the growing season in Sultan?
Measured between 28°F hard freezes, Sultan sees about 267 frost-free days — roughly Feb 28 through Nov 22, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Mar 21 to Nov 8, about 232 days.
Is the soil safe to grow vegetables in Sultan?
The federal record around Sultan is a meaningful one — 260 documented sites, mostly Nitrate entries (118), the nearest Superfund 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 Sultan?
From about Oct 23 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 22 (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 22. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Sultan's scale — its 8b band and its 267-day season. Your yard writes its own version of Sultan'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 Sultan’s own scale
6 of the readings below were taken at Sultan's own scale — its own ~267-day season between 28°F freezes, the 2,136 acres it covers and 260 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Sultan's own USDA hardiness band, zones 8bUSDA PHZM 2023
- Sultan's own 28°F hard-freeze dates, about Feb 28 and Nov 22 and the ~267-day span between themNOAA 1991–2020 Climate Normals
- 260 documented contamination sites on the federal record near Sultan, the closest Superfund record about 0.5 miles out from the town centreFederal environmental registers
- Sultan's boundary and the 2,136 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 8b and a ~267-day seasonGrowable Ground crop-matching engine
- Sultan 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 Sultan's 2,136 acres read through its county's SSURGO summaryfrom Snohomish County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Snohomish 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 Snohomish County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Sultan's 2,136 acreswhy one lot differs from the next →
- Which side of Sultan you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 2,136 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Superfund 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 Sultan-wide figureread your own land →
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