The Gallatin Valley spans USDA hardiness zone 5a — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
Southwest Montana's Gallatin Valley, the Bozeman-area basin, sits in USDA zone 5a with a short ~114-day frost-free growing season — the last spring frost typically holds until early June and the first fall frost returns by late September. A short list that earns its place here — potato, lentil, rhubarb, and cherry — with any one site's soil, sun, and drainage making the final cut.
The Gallatin Valley spans Montana.
Your yard isn't all of the Gallatin Valley.
The Gallatin Valley spans USDA zones 5a, but your parcel sits in exactly one — and slope, tree cover, and low spots nudge it further. 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 Gallatin Valley — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
The Gallatin Valley — the short answer
The Gallatin Valley: USDA zones 5a, 114 frost-free days, in Montana.
- USDA zones
- 5a
- USDA PHZM 2023, aggregated over the footprint
- Frost-free season
- 114 days
- NOAA Regional Climate Centers ACIS, 1991–2020
- Counties
- 1
- US Census TIGER/Line 2025
- Region type
- County cluster
- Growable Ground growing-region registry
Region boundary: Growable Ground growing-region registry — curated county clusters, EPA Level III ecoregions, and town clusters drawn finer than any county. Where a region publishes no measured season, no season figure is shown.
Hardiness Zone Range
What Grows in the Gallatin Valley
Plants matched to the Gallatin Valley's USDA zones 5a, ordered by how much hardiness margin each has across the region — the ones with room to spare at both ends of this band lead. Each links to its full growing profile.
Native Plants of the Gallatin Valley
Plants the USDA PLANTS Database documents as native and present in this region’s state, kept only where the published hardiness range meets the Gallatin Valley’s USDA zones 5a — closest range match first. Presence is recorded by state, so a plant can be documented across the state and still be scarce in your corner of the region.
The ground across the Gallatin Valley
The USDA soil survey maps this ground county by county. These are those records weighted by land area across one member county — this region’s own profile, not a state figure.
The ground is predominantly Mollisols, at 49% of mapped acres, followed by Inceptisols (25%), Alfisols (22%) and Entisols (4%). Six soil orders appear somewhere inside the footprint, which is the honest reason a regional soil answer only goes so far. The most extensive named soils are Brocko, Amesha, and Amsterdam.
75% of those acres are well drained, and another 8% somewhat excessively drained, 5% somewhat poorly drained. Topsoil pH runs 6.4–7.2 in that county’s own record. 3% of the footprint is classed prime farmland.
Soil order
Mollisols
Drainage
Well drained
Topsoil pH
6.4–7.2
Hydric soils
3%
Soil changes across a driveway, so which of these your own ground sits on is a parcel question rather than a regional one. soil types explained.
USDA NRCS SSURGO via Soil Data Access
What this means for growing in the Gallatin Valley
The soil survey reads this ground county by county, and the readings above are those records summed across the Gallatin Valley. Here is what they mean for a garden here — and the move an experienced grower makes about each one.
Drainage
From county records75% of the mapped acres across the Gallatin Valley are well drained — ground that drains quickly. That is area-weighted across its one mapped county.
The upside is soil you can work early in spring and roots that never drown; the cost is that fast-draining ground dries out fast and leaches nutrients away before plants can use them.
Work in compost and mulch to hold moisture and feed, and water more often in short doses than deep and rarely.
USDA NRCS SSURGO
Surface pH
From county recordsTopsoil across the Gallatin Valley runs pH 6.4–7.2 — near neutral in the one record covering it.
This is the range most vegetables prefer — one correction you probably do not have to make, which is genuinely good news for a new bed.
Keep it there with compost rather than lime or sulfur, and only amend if your own soil test says otherwise.
USDA NRCS SSURGO
Safe to Grow Here?
What the federal record shows across the Gallatin Valley — and how to grow with it.
Across the Gallatin Valley's 1 county the federal record holds 1,041 documented sites, mostly Nitrate (534), Underground Storage Tanks (302) and Brownfields (156). The heaviest single county is Gallatin County, with 1,041.
That is a regional count, not a reading of any one lot — proximity to a documented site is information, not a diagnosis. Open the map outlined to the Gallatin Valley to see which records sit where you actually grow.
Sources Checked
Summed across the county in the Gallatin Valley
A note from Gnorman
What an experienced grower watches for around here
In and around the Gallatin Valley, Nitrate runs higher than the national average — 534 sites across the county in the Gallatin Valley. 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).
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
Your land is one point inside the Gallatin Valley
Everything above resolves to the Gallatin Valley as a whole — a footprint spanning USDA zones 5a. Your parcel sits in exactly one of them. 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 region 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 regional average.
Your Lot vs the Gallatin Valley Average
Gallatin Valley Average
- ●USDA Zones 5a, averaged across Gallatin Valley
- ●One soil character for all of Gallatin Valley
- ●State-average frost dates
YOUR Parcel
- ✓Your exact zone, not Gallatin Valley's 5a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in the Gallatin Valley
Pull a site-specific report for your exact address in the Gallatin Valley — soil, sun, drainage, frost risk, contamination, and scored plant recommendations.
Three things about your lot that Gallatin Valley averages can't show:
We read public map data around The Gallatin Valley — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Gallatin Valley average
How we know this about the Gallatin Valley
The boundary: a cluster of neighboring counties. Growing regions have no official boundary, so this footprint is our published one, and every figure on this page was measured over the counties inside it rather than borrowed from the state around it.
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, aggregated across the footprint; the growing season from NOAA Regional Climate Centers ACIS 1991–2020 28°F normals, read at each member’s own record; boundaries from US Census TIGER/Line 2025; the contamination record from the federal sources named in that beat above; the soil from the USDA NRCS SSURGO survey, read at each member county’s own record and weighted to this footprint by land area. Where a member carries no record of its own, it is absent from the figure rather than filled in.
Common questions about the Gallatin Valley
What hardiness zone is the Gallatin Valley?
The Gallatin Valley spans USDA hardiness zones 5a, aggregated from the USDA Agricultural Research Service Plant Hardiness Zone Map 2023 across the region's counties. Zones reflect average annual extreme minimum temperatures from 1991–2020 data.
What grows well in the Gallatin Valley?
The Gallatin Valley's conditions suit plants such as Potato, Lentil, Rhubarb, Cherry, Ponderosa Pine. What actually thrives on any one site still turns on its specific soil, sun, and drainage — we score each plant against the real conditions at your address.
How is the Gallatin Valley defined?
The Gallatin Valley is defined here as a curated cluster of 1 neighboring counties that share a growing character. Growing regions have no official boundary, so this footprint is our published one — every county in it is named on this page.
Which states does the Gallatin Valley cover?
The Gallatin Valley spans Montana. Each state's full growing guide is linked on this page.
What other growing regions cover the same states?
The Hi-Line, The Yellowstone Valley, The Rocky Mountain Front / Great Falls Chinook Belt, Bitterroot Valley, Flathead Valley, and Paradise Valley share at least one state with the Gallatin Valley. Growing regions overlap and interlock — a single address can sit inside more than one, which is why the precise read is always the parcel, not the region.
What this page reads at the Gallatin Valley’s own scale
5 of the readings below were taken at the Gallatin Valley's own scale — the zone 5a band across its footprint and 1,041 documented federal contamination records across its one county, 1,041 of them in Gallatin County alone; one is borrowed from a wider read, named and linked below.
Measured here
- The USDA hardiness band 5a aggregated across the footprint's one countyUSDA PHZM 2023
- The boundary itself — the 1 county this region is curated fromGrowable Ground subregion registry
- The growing character that makes this region distinct from the states it crossesGrowable Ground subregion registry
- The federal contamination record over the whole footprint — 1,041 documented federal contamination records across its one county, 1,041 of them in Gallatin County aloneEPA, USGS and USDA federal site records
- The soil order mix across the footprint — 49% Mollisols, topsoil pH 6.4–7.2, area-weighted across its one mapped countyUSDA NRCS SSURGO
Inherited from a wider read
- The candidate plant list — its state's curated sets, merged and filtered to zones 5afrom Montana
What this page can’t tell you
- Frost dates — they swing too far across a footprint this size to quote as one regional numberfrost dates explained →
- Which of those soils your own ground sits on — the survey maps them county-wide, and they change across a drivewaysoil types explained →
- The soil pH, drainage, sun hours, and frost pockets on one specific lotwhy one lot differs from the next →
Explore the Gallatin Valley
State growing guides
Counties in this region
Other growing regions across Montana
Montana's coldest, driest strip — the northern-border county tier along US Highway 2 and the BNSF (old Great Northern) line — and the only Growable Ground region reaching USDA zone 3b: the Daniels–Sheridan–Roosevelt corner sits at 3b with just 142–146 frost-free days, a full zone colder than the 5a–6a mountain valleys captured elsewhere in the state. The western and central counties run 4a with 140–159 frost-free days. This is semi-arid dryland-wheat country with extreme winter minima and wide day-to-night diurnal swings; chinook winds moderate only the Glacier–Toole western end, leaving the shortest, most cold-hardy growing palette anywhere in Montana. None of that growing reality is visible on the sprawling statewide page.
Montana's longest growing season sits at its coldest-looking zones. The Yellowstone River bottomland from Billings down to Sidney runs 153-166 frost-free days (county_data.json) across USDA zones 4a-4b — a genuinely longer window than the state's 5a-6a mountain valleys, which sit in warmer zones but freeze sooner (Gallatin 114, Madison 117, Ravalli 146 frost-free days). That long, irrigated plains river-bottom season is what carries the corridor's sugar beets, corn, and full-season vegetables, and it is a distinctly different growing experience from Montana's SW/NW mountain valleys or the Hi-Line that a statewide average flattens away.
Where the northern plains slam into the Rocky Mountain Front, chinook winds rewrite the rules of a zone-4 winter. Great Falls earns its "banana belt of the north" name because these warm, dry downslope gales can lift a February morning tens of degrees in an hour — sparing tender crowns the deep cold the Hi-Line just east endures. The same wind is the catch: it desiccates exposed evergreens and perennials and whipsaws plantings through thaw-freeze cycles that split bark and heave roots. Here the decisive question isn't your zone (4a–4b, roughly 140–159 frost-free days) but your parcel's exposure to the Front — which slopes, shelterbelts, and wind-lees the chinook finds, and which it spares.
The Bitterroot Valley runs roughly 95 miles along the Bitterroot River between the Bitterroot Range and the Sapphire Mountains, spanning Ravalli and Missoula counties (USGS) across USDA hardiness zones 5b-6a, where a short 137-to-146-day frost-free season closes early: both counties typically see first frost by late September.
A mountain-ringed northwest Montana valley whose big lake buffers the cold — sweet cherries on the lakeshore benches, with mint, grain, and hay on the valley floor.
Paradise Valley traces the Yellowstone River through Montana's Park County, where USDA zone 5a and a roughly 125-day frost-free season — last frost in late May, first frost in late September — shape a short, high-elevation growing window.