Pompeys Pillar, 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.
On paper, cabbage, cranberry, turkish rocket, and collard greens all suit these conditions — on the ground, soil, sun, and drainage make the final call.
Even in Pompeys Pillar, 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 Pompeys Pillar 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 Pompeys Pillar — soil, climate, flood, and parcel records. How we handle your address.
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Pompeys Pillar — the short answer
Pompeys Pillar, Montana: USDA zone 4b, about 163 days between hard freezes, across 125 acres of town.
- USDA zone
- 4b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 26
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 6
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~163
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 125 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 Pompeys Pillar's average, not your lot's — a low corner or a tree line moves it. Against Pompeys Pillar's 163-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Pompeys Pillar
Each reading below is measured for Pompeys Pillar itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredPompeys Pillar runs about 163 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
MeasuredPompeys Pillar 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 Pompeys Pillar is in
Pompeys Pillar sits in the Northwestern Great Plains — EPA Level III, inside the wider Great Plains. That is read at Pompeys Pillar's own centroid rather than borrowed from Yellowstone County.
What Grows in Pompeys Pillar
Every plant below cleared Pompeys Pillar's own zone 4b and its 163-day season. Each card opens that plant's Montana profile. How we score.
Is it too late to plant in Pompeys Pillar?
Too late for some crops, right on time for others — a growing season is a sequence, not a deadline. Cool-season crops can go in from around Mar 29; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 26 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 6 — long-season crops need about 90 days of runway, quick greens only 30. Late in the year the fall bench takes over — quick greens, radishes, and garlic that repays you next summer.
What's on the federal record near Pompeys Pillar
Closest first, within ~10 miles of Pompeys Pillar. Listing isn't leaking, and distance isn't exposure.
- SERVICE GARAGEUnderground Storage Tanks · 650 ft
- 03N30E10CDBC01Nitrate · 2.4 mi
- BN POMPEYS PILLARUnderground Storage Tanks · 2.5 mi
- 9 M OAR LOCKUnderground Storage Tanks · 2.5 mi
- POMPEYS PILLAR RADIO SITEUnderground Storage Tanks · 2.5 mi
- 3N-30E-30baa01Nitrate · 4.2 mi
- 03N31E04DBDD01Nitrate · 4.9 mi
- 3N-29E-28cad01Nitrate · 8.3 mi
- 04N29E12C 01Nitrate · 8.9 mi
- 03N29E08DDAC01Nitrate · 9.0 mi
- HUNTLEY PROJECT IRRIGATION DISTUnderground Storage Tanks · 9.8 mi
Measured from Pompeys Pillar'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 Pompeys Pillar.
Total Sites
17
within ~10 miles of Pompeys Pillar
Risk Level
Low
Highest-severity
12 nitrate monitoring sites
Severity Distribution
within ~10 miles of Pompeys Pillar
Highest-Severity Sites
Know Before You Grow
- •On a private well, test for nitrates: above 10 mg/L the water needs treatment before irrigating.
- •Underground tanks leak petroleum as they age — near a former filling station, test the soil.
Check your specific parcel in Pompeys Pillar
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 Pompeys Pillar average
Your land is one point inside Pompeys Pillar
Everything above resolves to Pompeys Pillar as a whole — one PHZM band and one 28°F frost record, read across 125 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 Pompeys Pillar Average
Pompeys Pillar Average
- ●USDA Zones 4b, averaged across Pompeys Pillar
- ●One soil character for all of Pompeys Pillar
- ●Frost dates read at Pompeys Pillar's scale: Apr 26 to Oct 6
YOUR Parcel
- ✓Your exact zone, not Pompeys Pillar's 4b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Pompeys Pillar
Pull a site-specific report for your exact address in Pompeys Pillar, Montana — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Pompeys Pillar averages can't show:
We read public map data around Pompeys Pillar — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Pompeys Pillar average
How we know this about Pompeys Pillar
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 Pompeys Pillar’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 Pompeys Pillar
When does frost risk typically end in Pompeys Pillar?
The last hard freeze (28°F) in Pompeys Pillar typically lands around Apr 26, 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 17.
When is the first frost in Pompeys Pillar?
The first hard freeze (28°F) in Pompeys Pillar typically arrives around Oct 6, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 22, so the watching starts about Sep 6 — about 163 days after the spring freeze cleared.
How long is the growing season in Pompeys Pillar?
Measured between 28°F hard freezes, Pompeys Pillar sees about 163 frost-free days — roughly Apr 26 through Oct 6, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 17 to Sep 22, about 128 days.
Is the soil safe to grow vegetables in Pompeys Pillar?
The federal record around Pompeys Pillar is light — 17 documented sites across the 9 federal source types we checked, mostly Nitrate entries (12), the nearest Underground Storage Tanks record about 0.1 miles 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 Pompeys Pillar?
From about Sep 6 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 6 (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 6. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Pompeys Pillar's scale — its 4b band and its 163-day season. Your yard writes its own version of Pompeys Pillar'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 Pompeys Pillar’s own scale
6 of the readings below were taken at Pompeys Pillar's own scale — its own ~163-day season between 28°F freezes, the 125 acres it covers and 17 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Pompeys Pillar's own USDA hardiness band, zones 4bUSDA PHZM 2023
- Pompeys Pillar's own 28°F hard-freeze dates, about Apr 26 and Oct 6 and the ~163-day span between themNOAA 1991–2020 Climate Normals
- 17 documented contamination sites on the federal record near Pompeys Pillar, the closest Underground Storage Tanks record about 0.1 miles out from the town centreFederal environmental registers
- Pompeys Pillar's boundary and the 125 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 4b and a ~163-day seasonGrowable Ground crop-matching engine
- The ecoregion at Pompeys Pillar's own centroid, the Northwestern Great PlainsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Pompeys Pillar's 125 acres read through its county's SSURGO summaryfrom Yellowstone County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Yellowstone 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 Yellowstone County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Pompeys Pillar's 125 acreswhy one lot differs from the next →
- Which side of Pompeys Pillar you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 125 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks 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 Pompeys Pillar-wide figureread your own land →
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