Fairfield, Montana, sits in USDA hardiness zone 4b — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
A short list that earns its place here — cabbage, cranberry, turkish rocket, and collard greens — with any one site's soil, sun, and drainage making the final cut.
Even in Fairfield, 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 Fairfield 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 Fairfield — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Fairfield — the short answer
Fairfield, Montana: USDA zone 4b, about 164 days between hard freezes, across 202 acres of town.
- USDA zone
- 4b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 30
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 11
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~164
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 202 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 4b is Fairfield's average, not your lot's — a low corner or a tree line moves it. Against Fairfield's 164-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Fairfield
Each reading below is measured for Fairfield itself — here is what it means for a garden here, and the move an experienced grower makes about it.

Season length
MeasuredFairfield runs about 164 days between hard freezes — a moderate growing season.
There is room for the full run of cool-season crops plus a warm-season main crop, but the calendar is tight enough that a late spring or early fall frost still decides how much finishes.
Time warm-season transplants to your last hard freeze, and a few weeks of season extension turns a near-miss harvest into a sure one.
NOAA 1991–2020 Climate Normals

Winter hardiness
MeasuredFairfield sits in USDA hardiness zone 4b.
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 Fairfield is in
Fairfield sits in the Northwestern Glaciated Plains — EPA Level III, inside the wider Great Plains. That is read at Fairfield's own centroid rather than borrowed from Teton County.
What Grows in Fairfield
Every plant below cleared Fairfield's own zone 4b and its 164-day season. Each card opens that plant's Montana profile. How we score.






























Is it too late to plant in Fairfield?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Apr 2; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 30 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 11 — long-season crops need about 90 days of runway, quick greens only 30. As the window narrows, the plantings just get faster — fall brassicas, then greens, then garlic to finish.
What's on the federal record near Fairfield
Closest first, within ~10 miles of Fairfield. Listing isn't leaking, and distance isn't exposure.
- MOUNTAIN VIEW COOP THE STOREUnderground Storage Tanks · 400 ft
- DIRKES CHEVROLET PONTIAC OLDSBrownfields · 450 ft
- DIRKES INC FAIRFIELDUnderground Storage Tanks · 500 ft
- MILLS MOTORSBrownfields · 500 ft
- MILLS MOTOR CO INCUnderground Storage Tanks · 500 ft
- MOUNTAIN VIEW COOP FAIRFIELDUnderground Storage Tanks · 700 ft
- TETON COUNTY AIRPORT COMMISSIONUnderground Storage Tanks · 800 ft
- OAKLEY BROTHERS TRUCKINGUnderground Storage Tanks · 800 ft
- LEONETTE R JAUMOTTE FAIRFIELDUnderground Storage Tanks · 800 ft
- TETON COUNTY SHOPUnderground Storage Tanks · 800 ft
- GORDON YOUNGUnderground Storage Tanks · 800 ft
- GREENFIELDS IRRIGATION DISTRICT USTUnderground Storage Tanks · 1200 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Fairfield'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 Fairfield.
Total Sites
126
within ~10 miles of Fairfield
Risk Level
Moderate
Highest-severity
1 concentrated animal feeding operation
Sources Checked
within ~10 miles of Fairfield
Severity Distribution
within ~10 miles of Fairfield
Highest-Severity Sites

A note from Gnorman
What an experienced grower watches for around here
In and around Fairfield, Nitrate runs higher than the national average — 90 sites within ~10 miles of Fairfield. Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
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 Fairfield
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 Fairfield average
Your land is one point inside Fairfield
Everything above resolves to Fairfield as a whole — one PHZM band and one 28°F frost record, read across 202 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 Fairfield Average
Fairfield Average
- ●USDA Zones 4b, averaged across Fairfield
- ●One soil character for all of Fairfield
- ●Frost dates read at Fairfield's scale: Apr 30 to Oct 11
YOUR Parcel
- ✓Your exact zone, not Fairfield's 4b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Fairfield
Pull a site-specific report for your exact address in Fairfield, Montana — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Fairfield averages can't show:
We read public map data around Fairfield — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Fairfield average
How we know this about Fairfield
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 Fairfield’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 Fairfield
When does frost risk typically end in Fairfield?
The last hard freeze (28°F) in Fairfield typically lands around Apr 30, 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 May 21.
When is the first frost in Fairfield?
The first hard freeze (28°F) in Fairfield typically arrives around Oct 11, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 27, so the watching starts about Sep 11 — about 164 days after the spring freeze cleared.
How long is the growing season in Fairfield?
Measured between 28°F hard freezes, Fairfield sees about 164 frost-free days — roughly Apr 30 through Oct 11, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 21 to Sep 27, about 129 days.
Is the soil safe to grow vegetables in Fairfield?
The federal record around Fairfield shows 126 documented sites, mostly Nitrate entries (90), the nearest Underground Storage Tanks record under a tenth of a mile out — a typical footprint for a growing area, and proximity to a documented site is information, not a diagnosis of any one yard. It's worth seeing which recorded sites sit closest to where you grow, and testing the soil before new food beds near any of them.
How do I protect my plants from frost in Fairfield?
From about Sep 11 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 11 (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 11. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Fairfield's scale — its 4b band and its 164-day season. Your yard writes its own version of Fairfield'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 Fairfield’s own scale
6 of the readings below were taken at Fairfield's own scale — its own ~164-day season between 28°F freezes, the 202 acres it covers and 126 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Fairfield's own USDA hardiness band, zones 4bUSDA PHZM 2023
- Fairfield's own 28°F hard-freeze dates, about Apr 30 and Oct 11 and the ~164-day span between themNOAA 1991–2020 Climate Normals
- 126 documented contamination sites on the federal record near Fairfield, the closest Underground Storage Tanks record under a tenth of a mile out from the town centreFederal environmental registers
- Fairfield's boundary and the 202 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 4b and a ~164-day seasonGrowable Ground crop-matching engine
- The ecoregion at Fairfield's own centroid, the Northwestern Glaciated PlainsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Fairfield's 202 acres read through its county's SSURGO summaryfrom Teton County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Teton County
- The growing challenges every Montana grower plans around — written at state scale, so they stay on the state guidefrom Montana
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Teton County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Fairfield's 202 acreswhy one lot differs from the next →
- Which side of Fairfield you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 202 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 Fairfield-wide figureread your own land →
