Lewistown, Montana, sits in USDA hardiness zone 4b — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
Expect cabbage, cranberry, cilantro, and collard greens to be strong candidates here; the deciding factors on any one parcel stay local — soil, sun, and drainage.
Even in Lewistown, 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 Lewistown 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 Lewistown — soil, climate, flood, and parcel records. How we handle your address.
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Lewistown — the short answer
Lewistown, Montana: USDA zone 4b, about 149 days between hard freezes, across 4K acres of city.
- USDA zone
- 4b
- USDA PHZM 2023
- Last hard freeze (28°F)
- May 7
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 3
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~149
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 4K 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 Lewistown's average, not your lot's — a low corner or a tree line moves it. Against Lewistown's 149-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Lewistown
Each reading below is measured for Lewistown itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredLewistown runs about 149 days between hard freezes — a short growing season.
Long-maturing crops like melons, sweet potatoes, and winter squash can run out of runway before the first hard freeze, ripening late or not at all.
Lead with fast-maturing varieties, and stretch the season on both ends with cold frames, low tunnels, or a greenhouse.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredLewistown 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 Lewistown is in
Lewistown sits in the Northwestern Great Plains — EPA Level III, inside the wider Great Plains. That is read at Lewistown's own centroid rather than borrowed from Fergus County.
What Grows in Lewistown
Every plant below cleared Lewistown's own zone 4b and its 149-day season. Each card opens that plant's Montana profile. How we score.
Is it too late to plant in Lewistown?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Apr 9; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near May 7 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 3 — long-season crops need about 90 days of runway, quick greens only 30. Even here the calendar’s edges hold value: thirty-day greens late in the window, then garlic and a rested bed for spring.
What's on the federal record near Lewistown
Closest first, within ~10 miles of Lewistown. Listing isn't leaking, and distance isn't exposure.
- NEWTON AVIATIONBrownfields · 650 ft
- SKYLINE AVIATIONUnderground Storage Tanks · 1000 ft
- MT ARNG LEWISTOWN READINESS CENTERBrownfields · 1400 ft
- C M RUSSELL NATL WILDLIFE RFGEUnderground Storage Tanks · 1500 ft
- MT DOT LEWISTOWNBrownfields · 1500 ft
- LEWISTOWN AIRPORT OLD HANGERBrownfields · 1600 ft
- UPS - LEWISTOWN CENTERBrownfields · 1700 ft
- RAHN AUTOMOTIVEBrownfields · 1700 ft
- BLUE SKY AVIATION INCBrownfields · 1800 ft
- 15N18E16CCC 01Nitrate · 2100 ft
- FERGUS COUNTY ROAD & BRIDGE DEPTUnderground Storage Tanks · 2400 ft
- FERGUS COUNTY ROAD DEPTBrownfields · 2500 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Lewistown'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 Lewistown.
Total Sites
272
within ~10 miles of Lewistown
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
within ~10 miles of Lewistown
Severity Distribution
within ~10 miles of Lewistown
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Lewistown, Nitrate runs higher than the national average — 162 sites within ~10 miles of Lewistown. It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around 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 Lewistown
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 Lewistown average
Your land is one point inside Lewistown
Everything above resolves to Lewistown as a whole — one PHZM band and one 28°F frost record, read across 4K 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 Lewistown Average
Lewistown Average
- ●USDA Zones 4b, averaged across Lewistown
- ●One soil character for all of Lewistown
- ●Frost dates read at Lewistown's scale: May 7 to Oct 3
YOUR Parcel
- ✓Your exact zone, not Lewistown's 4b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Lewistown
Pull a site-specific report for your exact address in Lewistown, Montana — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Lewistown averages can't show:
We read public map data around Lewistown — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Lewistown average
How we know this about Lewistown
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 Lewistown’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 Lewistown
When does frost risk typically end in Lewistown?
The last hard freeze (28°F) in Lewistown typically lands around May 7, 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 28.
When is the first frost in Lewistown?
The first hard freeze (28°F) in Lewistown typically arrives around Oct 3, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 19, so the watching starts about Sep 3 — about 149 days after the spring freeze cleared.
How long is the growing season in Lewistown?
Measured between 28°F hard freezes, Lewistown sees about 149 frost-free days — roughly May 7 through Oct 3, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 28 to Sep 19, about 114 days.
Is the soil safe to grow vegetables in Lewistown?
The federal record around Lewistown is a meaningful one — 272 documented sites, mostly Nitrate entries (162), the nearest Brownfields record about 0.1 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 gardeners stretch the season in Lewistown?
With about 149 frost-free days between hard freezes, Lewistown rewards the classic extension moves: floating row cover buys roughly two to four extra weeks at each shoulder — on this season that is a working window nearer 177 to 205 days — and cold frames or low tunnels buy more. Starting transplants indoors ahead of the May 7 hard-freeze normal stretches the season without touching the calendar.
Everything above is measured at Lewistown's scale — its 4b band and its 149-day season. Your yard writes its own version of Lewistown'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 Lewistown’s own scale
6 of the readings below were taken at Lewistown's own scale — its own ~149-day season between 28°F freezes, the 3,662 acres it covers and 272 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Lewistown's own USDA hardiness band, zones 4bUSDA PHZM 2023
- Lewistown's own 28°F hard-freeze dates, about May 7 and Oct 3 and the ~149-day span between themNOAA 1991–2020 Climate Normals
- 272 documented contamination sites on the federal record near Lewistown, the closest Brownfields record about 0.1 miles out from the town centreFederal environmental registers
- Lewistown's boundary and the 3,662 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 4b and a ~149-day seasonGrowable Ground crop-matching engine
- The ecoregion at Lewistown's own centroid, the Northwestern Great PlainsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Lewistown's 3,662 acres read through its county's SSURGO summaryfrom Fergus County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Fergus 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 Fergus County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Lewistown's 3,662 acreswhy one lot differs from the next →
- Which side of Lewistown you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 3,662 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields record about 0.1 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 Lewistown-wide figureread your own land →
More in Montana
Wider growing context
What grows across MontanaLewistown sits outside our named growing regions, so Montana as a whole is its closest context here.
Nearby growing guides