Colton, Washington, sits in USDA hardiness zone 7a — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
The conditions favor cabbage, pawpaw, california poppy, and collard greens, among others — though every individual site edits that list with its own soil, sun, and drainage.
Even in Colton, 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 Colton 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 Colton — soil, climate, flood, and parcel records. How we handle your address.
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Colton — the short answer
Colton, Washington: USDA zone 7a, about 207 days between hard freezes, across 395 acres of town.
- USDA zone
- 7a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 4
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 28
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~207
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 395 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 Colton's average, not your lot's — a low corner or a tree line moves it. Against Colton's 207-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Colton
Each reading below is measured for Colton itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredColton 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
MeasuredColton 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 Colton is in
Colton sits in the Columbia Plateau — EPA Level III, inside the wider North American Deserts. That is read at Colton's own centroid rather than borrowed from Whitman County.
What Grows in Colton
Every plant below cleared Colton'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 Colton?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Mar 7; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 4 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 28 — long-season crops need about 90 days of runway, quick greens only 30. A long window like this one runs successions deep into fall — and even its last weeks take quick greens and garlic.
What's on the federal record near Colton
Closest first, within ~10 miles of Colton. Listing isn't leaking, and distance isn't exposure.
- WHITMAN COUNTY RD DEPTUnderground Storage Tanks · 200 ft
- COLTON SCHOOL DISTRICT NO 306Underground Storage Tanks · 400 ft
- WILBUR-ELLIS COMPANY COLTONBrownfields · 2000 ft
- GENE SCHULTHEIS FARMS INCUnderground Storage Tanks · 0.8 mi
- ED DRUFFEL FARMS INCUnderground Storage Tanks · 1.0 mi
- PHIL R DRUFFELUnderground Storage Tanks · 1.0 mi
- LARRY DRUFFEL FARMS INCUnderground Storage Tanks · 1.0 mi
- JOHNSON UNION WAREHOUSE COMPANYUnderground Storage Tanks · 1.0 mi
- HAROLD SCHULTHEIS & SONSUnderground Storage Tanks · 1.0 mi
- DICK JUTTEUnderground Storage Tanks · 1.0 mi
- RAY F BAUER INCUnderground Storage Tanks · 2.5 mi
- 12N/46E-07B02 LE22Nitrate · 2.5 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Colton'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 Colton.
Severity Distribution
within ~10 miles of Colton
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Colton, Underground Storage Tanks runs higher than the national average — 29 sites within ~10 miles of Colton. Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
Underground Storage Tanks: Underground storage tanks are the single most common source of soil contamination near homes and gardens.
Use raised beds with imported soil — this eliminates the primary soil-contact pathway.
Check your specific parcel in Colton
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 Colton average
Your land is one point inside Colton
Everything above resolves to Colton as a whole — one PHZM band and one 28°F frost record, read across 395 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 Colton Average
Colton Average
- ●USDA Zones 7a, averaged across Colton
- ●One soil character for all of Colton
- ●Frost dates read at Colton's scale: Apr 4 to Oct 28
YOUR Parcel
- ✓Your exact zone, not Colton's 7a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Colton
Pull a site-specific report for your exact address in Colton, Washington — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Colton averages can't show:
We read public map data around Colton — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Colton average
How we know this about Colton
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 Colton’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 Colton
When does frost risk typically end in Colton?
The last hard freeze (28°F) in Colton typically lands around Apr 4, 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 25.
When is the first frost in Colton?
The first hard freeze (28°F) in Colton typically arrives around Oct 28, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 14, so the watching starts about Sep 28 — about 207 days after the spring freeze cleared.
How long is the growing season in Colton?
Measured between 28°F hard freezes, Colton sees about 207 frost-free days — roughly Apr 4 through Oct 28, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 25 to Oct 14, about 172 days.
Is the soil safe to grow vegetables in Colton?
The federal record around Colton is light — 40 documented sites across the 9 federal source types we checked, mostly Underground Storage Tanks entries (29), the nearest Underground Storage Tanks record under a tenth of a mile out — and proximity to a documented site is information, not a diagnosis of any one yard. Growing food here starts from a strong position; a soil test before new food beds settles any site-specific question.
How do I protect my plants from frost in Colton?
From about Sep 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 Oct 28 (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 28. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Colton's scale — its 7a band and its 207-day season. Your yard writes its own version of Colton'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 Colton’s own scale
6 of the readings below were taken at Colton's own scale — its own ~207-day season between 28°F freezes, the 395 acres it covers and 40 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Colton's own USDA hardiness band, zones 7aUSDA PHZM 2023
- Colton's own 28°F hard-freeze dates, about Apr 4 and Oct 28 and the ~207-day span between themNOAA 1991–2020 Climate Normals
- 40 documented contamination sites on the federal record near Colton, the closest Underground Storage Tanks record under a tenth of a mile out from the town centreFederal environmental registers
- Colton's boundary and the 395 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 Colton's own centroid, the Columbia PlateauUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Colton's 395 acres read through its county's SSURGO summaryfrom Whitman County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Whitman 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 Whitman County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Colton's 395 acreswhy one lot differs from the next →
- Which side of Colton you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 395 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record under a tenth of a mile 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 Colton-wide figureread your own land →