Biddle, Montana, sits in USDA hardiness zone 4b — a zone band wide enough that plant choice, not possibility, is the interesting question.
Crops well matched to these conditions include cabbage, cranberry, turkish rocket, and collard greens — though what thrives on any one site still turns on its specific soil, sun, and drainage.
Even in Biddle, 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 Biddle 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 Biddle — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Biddle — the short answer
Biddle, Montana: USDA zone 4b, about 151 days between hard freezes, across 11K 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 4
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~151
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 11K 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 Biddle's average, not your lot's — a low corner or a tree line moves it. Against Biddle's 151-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Biddle
Each reading below is measured for Biddle itself — here is what it means for a garden here, and the move an experienced grower makes about it.

Season length
MeasuredBiddle runs about 151 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
MeasuredBiddle 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 Biddle is in
Biddle sits in the Northwestern Great Plains — EPA Level III, inside the wider Great Plains. That is read at Biddle's own centroid rather than borrowed from Powder River County.
What Grows in Biddle
Every plant below cleared Biddle's own zone 4b and its 151-day season. Each card opens that plant's Montana profile. How we score.





























Is it too late to plant in Biddle?
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 4 — long-season crops need about 90 days of runway, quick greens only 30. Even past midsummer there is room for a true fall garden here, and garlic planted near the close carries the momentum into next year.
What's on the federal record near Biddle
Closest first, within ~10 miles of Biddle. Listing isn't leaking, and distance isn't exposure.
- CROSS RANCH MERCUnderground Storage Tanks · 1.4 mi
- T & R FARMING INCUnderground Storage Tanks · 5.4 mi
- 08S51E12DCBB01Nitrate · 5.7 mi
- 07S52E27ABBB01Nitrate · 6.8 mi
- 58-071-26da 01Nitrate · 8.4 mi
- 58-071-25dc 01Nitrate · 8.5 mi
- 07S51E34DBDB01Nitrate · 8.6 mi
- 07S52E10DBDC01Nitrate · 9.1 mi
- 09S51E21DBBB01Nitrate · 9.3 mi
- 07S52E11BBBB01Nitrate · 9.7 mi
Measured from Biddle'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 Biddle.
Severity Distribution
within ~10 miles of Biddle
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 Biddle
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 Biddle average
Your land is one point inside Biddle
Everything above resolves to Biddle as a whole — one PHZM band and one 28°F frost record, read across 11K 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 Biddle Average
Biddle Average
- ●USDA Zones 4b, averaged across Biddle
- ●One soil character for all of Biddle
- ●Frost dates read at Biddle's scale: May 6 to Oct 4
YOUR Parcel
- ✓Your exact zone, not Biddle's 4b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Biddle
Pull a site-specific report for your exact address in Biddle, Montana — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Biddle averages can't show:
We read public map data around Biddle — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Biddle average
How we know this about Biddle
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 Biddle’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 Biddle
When does frost risk typically end in Biddle?
The last hard freeze (28°F) in Biddle 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 Biddle?
The first hard freeze (28°F) in Biddle typically arrives around Oct 4, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 20, so the watching starts about Sep 4 — about 151 days after the spring freeze cleared.
How long is the growing season in Biddle?
Measured between 28°F hard freezes, Biddle sees about 151 frost-free days — roughly May 6 through Oct 4, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 27 to Sep 20, about 116 days.
Is the soil safe to grow vegetables in Biddle?
The federal record around Biddle is light — 18 documented sites across the 9 federal source types we checked, mostly Nitrate entries (16), the nearest Underground Storage Tanks record about 1.4 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 Biddle?
From about Sep 4 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 4 (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 4. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Biddle's scale — its 4b band and its 151-day season. Your yard writes its own version of Biddle'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 Biddle’s own scale
6 of the readings below were taken at Biddle's own scale — its own ~151-day season between 28°F freezes, the 10,956 acres it covers and 18 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Biddle's own USDA hardiness band, zones 4bUSDA PHZM 2023
- Biddle's own 28°F hard-freeze dates, about May 6 and Oct 4 and the ~151-day span between themNOAA 1991–2020 Climate Normals
- 18 documented contamination sites on the federal record near Biddle, the closest Underground Storage Tanks record about 1.4 miles out from the town centreFederal environmental registers
- Biddle's boundary and the 10,956 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 4b and a ~151-day seasonGrowable Ground crop-matching engine
- The ecoregion at Biddle's own centroid, the Northwestern Great PlainsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Biddle's 10,956 acres read through its county's SSURGO summaryfrom Powder River County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Powder River 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 Powder River County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Biddle's 10,956 acreswhy one lot differs from the next →
- Which side of Biddle you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 10,956 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 1.4 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 Biddle-wide figureread your own land →
More in Montana
Wider growing context
What grows across MontanaBiddle sits outside our named growing regions, so Montana as a whole is its closest context here.
