Hays, Montana, sits in USDA hardiness zone 4b — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
Among the crops suited to this profile: cabbage, cranberry, turkish rocket, and collard greens. The site-level story — soil, sun, drainage — decides the rest.
Even in Hays, 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 Hays 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 Hays — soil, climate, flood, and parcel records. How we handle your address.
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Hays — the short answer
Hays, Montana: USDA zone 4b, about 150 days between hard freezes, across 17K acres of town.
- USDA zone
- 4b
- USDA PHZM 2023
- Last hard freeze (28°F)
- May 6
- 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
- ~150
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 17K 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 Hays's average, not your lot's — a low corner or a tree line moves it. Against Hays's 150-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Hays
Each reading below is measured for Hays itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredHays runs about 150 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
MeasuredHays 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 Hays is in
Hays sits in the Middle Rockies — EPA Level III, inside the wider Northwestern Forested Mountains. That is read at Hays's own centroid, and it is not what its county reads: Blaine County is mostly Northwestern Glaciated Plains. The wider page above you is answering a different question about different ground.
What Grows in Hays
Every plant below cleared Hays's own zone 4b and its 150-day season. Each card opens that plant's Montana profile. How we score.
Is it too late to plant in Hays?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Apr 8; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near May 6 (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. The tail of the season still works: sixty-day crops into late summer, quick greens after, garlic last of all.
What's on the federal record near Hays
Closest first, within ~10 miles of Hays. Listing isn't leaking, and distance isn't exposure.
- 26N24E17BAAD01Nitrate · 1600 ft
- 26N24E20BBCB01Nitrate · 0.8 mi
- 26N24E19AACA01Nitrate · 1.3 mi
- 26N23E12ADDD01Nitrate · 1.8 mi
- 26N24E07BBDB02Nitrate · 1.8 mi
- 26N24E07BBDB01Nitrate · 1.8 mi
- 26N23E12DCBB02Nitrate · 2.0 mi
- 26N23E12DCBB01Nitrate · 2.0 mi
- 26N24E30BADB01Nitrate · 2.0 mi
- KING CREEKSuperfund · 2.1 mi
- BECKS GENERAL STOREUnderground Storage Tanks · 2.1 mi
- 26N23E24DDDB01Nitrate · 2.1 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Hays'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 Hays.
Total Sites
210
within ~10 miles of Hays
Risk Level
Elevated
Highest-severity
2 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Hays
Severity Distribution
within ~10 miles of Hays
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Hays, Nitrate runs higher than the national average — 188 sites within ~10 miles of Hays. 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 Hays
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 Hays average
Your land is one point inside Hays
Everything above resolves to Hays as a whole — one PHZM band and one 28°F frost record, read across 17K 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 Hays Average
Hays Average
- ●USDA Zones 4b, averaged across Hays
- ●One soil character for all of Hays
- ●Frost dates read at Hays's scale: May 6 to Oct 3
YOUR Parcel
- ✓Your exact zone, not Hays's 4b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Hays
Pull a site-specific report for your exact address in Hays, Montana — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Hays averages can't show:
We read public map data around Hays — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Hays average
How we know this about Hays
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 Hays’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 Hays
When does frost risk typically end in Hays?
The last hard freeze (28°F) in Hays typically lands around May 6, 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 27.
When is the first frost in Hays?
The first hard freeze (28°F) in Hays 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 150 days after the spring freeze cleared.
How long is the growing season in Hays?
Measured between 28°F hard freezes, Hays sees about 150 frost-free days — roughly May 6 through Oct 3, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 27 to Sep 19, about 115 days.
Is the soil safe to grow vegetables in Hays?
The federal record around Hays is a meaningful one — 210 documented sites, mostly Nitrate entries (188), the nearest Nitrate record about 0.3 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 Hays?
From about Sep 3 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 3 (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 3. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Hays's scale — its 4b band and its 150-day season. Your yard writes its own version of Hays'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 Hays’s own scale
6 of the readings below were taken at Hays's own scale — its own ~150-day season between 28°F freezes, the 17,341 acres it covers and 210 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Hays's own USDA hardiness band, zones 4bUSDA PHZM 2023
- Hays's own 28°F hard-freeze dates, about May 6 and Oct 3 and the ~150-day span between themNOAA 1991–2020 Climate Normals
- 210 documented contamination sites on the federal record near Hays, the closest Nitrate record about 0.3 miles out from the town centreFederal environmental registers
- Hays's boundary and the 17,341 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 4b and a ~150-day seasonGrowable Ground crop-matching engine
- Hays sits in the Middle Rockies — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Hays's 17,341 acres read through its county's SSURGO summaryfrom Blaine County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Blaine 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 Blaine County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Hays's 17,341 acreswhy one lot differs from the next →
- Which side of Hays you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 17,341 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Nitrate record about 0.3 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 Hays-wide figureread your own land →
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