White Swan, Washington, sits in USDA hardiness zone 7a — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
Reliable performers under these conditions include cabbage, pawpaw, california poppy, and collard greens; what your own ground favors still comes down to its soil, sun, and drainage.
Even in White Swan, 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 White Swan 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 White Swan — soil, climate, flood, and parcel records. How we handle your address.
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White Swan — the short answer
White Swan, Washington: USDA zone 7a, about 207 days between hard freezes, across 2K acres of town.
- USDA zone
- 7a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 1
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 25
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~207
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town 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 7a is White Swan's average, not your lot's — a low corner or a tree line moves it. Against White Swan's 207-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in White Swan
Each reading below is measured for White Swan itself — here is what it means for a garden here, and the move an experienced grower makes about it.

Season length
MeasuredWhite Swan runs about 207 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
MeasuredWhite Swan sits in USDA hardiness zone 7a.
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 White Swan is in
White Swan sits in the Columbia Plateau — EPA Level III, inside the wider North American Deserts. That is read at White Swan's own centroid rather than borrowed from Yakima County.
What Grows in White Swan
Every plant below cleared White Swan's own zone 7a and its 207-day season. Each card opens that plant's Washington profile. How we score.






























Is it too late to plant in White Swan?
For most of the year, no — what changes is which crops still fit the days remaining. Cool-season crops can go in from around Mar 4; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 1 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 25 — long-season crops need about 90 days of runway, quick greens only 30. Here the season winds down slowly: late sowings, a real autumn harvest, and garlic in the ground before the first hard freeze.
What's on the federal record near White Swan
Closest first, within ~10 miles of White Swan. Listing isn't leaking, and distance isn't exposure.
- US DOI FT SIMCOE JOB CORP CTRSuperfund · 0.5 mi
- WHITE SWAN FIRE RESPONSESuperfund · 0.6 mi
- YAKAMA BUSINESS AND TECH CENTERToxics Release Inventory · 1.0 mi
- 11N/16E-35J01Nitrate · 2.4 mi
- 11N/16E-25N01Nitrate · 2.5 mi
- 10N/17E-29A01Nitrate · 3.5 mi
- 10N/17E-27Q01Nitrate · 5.1 mi
- 10N/16E-21D01Nitrate · 5.2 mi
- 10N/16E-20E01Nitrate · 6.0 mi
- 10N/18E-06R04Nitrate · 6.2 mi
- 11N/18E-32D01Nitrate · 6.4 mi
- 10N/16E-19H01D1Nitrate · 6.4 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from White Swan'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 White Swan.
Total Sites
57
within ~10 miles of White Swan
Risk Level
Elevated
Highest-severity
2 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of White Swan
Severity Distribution
within ~10 miles of White Swan
Highest-Severity Sites

A note from Gnorman
What an experienced grower watches for around here
In and around White Swan, Nitrate runs higher than the national average — 50 sites within ~10 miles of White Swan. That's not a problem with your land — it's information about it.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in White Swan
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 White Swan average
Your land is one point inside White Swan
Everything above resolves to White Swan 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 town 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 White Swan Average
White Swan Average
- ●USDA Zones 7a, averaged across White Swan
- ●One soil character for all of White Swan
- ●Frost dates read at White Swan's scale: Apr 1 to Oct 25
YOUR Parcel
- ✓Your exact zone, not White Swan's 7a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in White Swan
Pull a site-specific report for your exact address in White Swan, Washington — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that White Swan averages can't show:
We read public map data around White Swan — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the White Swan average
How we know this about White Swan
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this town’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at White Swan’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 town grain anywhere on this page — there is no town-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 White Swan
When does frost risk typically end in White Swan?
The last hard freeze (28°F) in White Swan typically lands around Apr 1, 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 Apr 22.
When is the first frost in White Swan?
The first hard freeze (28°F) in White Swan typically arrives around Oct 25, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 11, so the watching starts about Sep 25 — about 207 days after the spring freeze cleared.
How long is the growing season in White Swan?
Measured between 28°F hard freezes, White Swan sees about 207 frost-free days — roughly Apr 1 through Oct 25, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 22 to Oct 11, about 172 days.
Is the soil safe to grow vegetables in White Swan?
The federal record around White Swan is a meaningful one — 57 documented sites, mostly Nitrate entries (50), 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 White Swan?
From about Sep 25 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 Oct 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 Oct 25. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at White Swan's scale — its 7a band and its 207-day season. Your yard writes its own version of White Swan'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 White Swan’s own scale
6 of the readings below were taken at White Swan's own scale — its own ~207-day season between 28°F freezes, the 1,707 acres it covers and 57 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- White Swan's own USDA hardiness band, zones 7aUSDA PHZM 2023
- White Swan's own 28°F hard-freeze dates, about Apr 1 and Oct 25 and the ~207-day span between themNOAA 1991–2020 Climate Normals
- 57 documented contamination sites on the federal record near White Swan, the closest Superfund record about 0.5 miles out from the town centreFederal environmental registers
- White Swan's boundary and the 1,707 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7a and a ~207-day seasonGrowable Ground crop-matching engine
- The ecoregion at White Swan's own centroid, the Columbia PlateauUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so White Swan's 1,707 acres read through its county's SSURGO summaryfrom Yakima County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Yakima 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 Yakima County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among White Swan's 1,707 acreswhy one lot differs from the next →
- Which side of White Swan you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 1,707 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 White Swan-wide figureread your own land →
