Big Stone County, in Minnesota, sits in USDA hardiness zone 4b — a zone band wide enough that plant choice, not possibility, is the interesting question.
These conditions suit cabbage, cranberry, turkish rocket, and collard greens — a starting list any specific site will trim or extend with its own soil, sun, and drainage.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Big Stone County holds more than one microclimate.
Soils and elevations shift across Big Stone County, so your frost dates and drainage aren't the county average. 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 Big Stone County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Big Stone County — the short answer
Big Stone County, Minnesota: USDA zone 4b, about 172 days between hard freezes, across 319K acres.
- USDA zone
- 4b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 21
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Oct 10
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~172
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 319K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are county 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 Big Stone County's average, not your lot's — a low corner or a tree line moves it. Against Big Stone County's 172-day season, see what your own ground reads.
Heat in Big Stone County
Across a year, Big Stone County accumulates about 2,300 growing degree days above 50°F, about 35 more than the middle Minnesota county — ahead of 49 of Minnesota’s 87 counties. Degree days are the heat a crop actually gets to work with — more of them is more room to ripen a long-season crop before the freeze closes the window.
Grounded in PRISM Climate Group, Oregon State University — 1991–2020 monthly normals
Soil in Big Stone County
Across Big Stone County, the ground is predominantly Mollisols, where Aazdahl, Hattie, and Esmond are the most extensive named soil series. The soil is generally moderately well drained with a clay loam surface. Topsoil pH runs about 7.0–7.9, slightly alkaline. Rainfall drains through hydrologic group C/D soils.
Soil order
Mollisols
Drainage
Moderately well drained
Prime farmland
48%
Hydric soils
30%
Soil still varies lot by lot — soil types explained.
How the ground varies across Big Stone County
The USDA soil survey maps 33% of Big Stone County as moderately well drained — but another 62% drains differently: 21% poorly drained, 20% well drained.
Aazdahl is the most extensive named soil at 12% of mapped acres, then Hattie (9%) and Esmond (7%).
Which of them your own lot sits on is a parcel question, not a county one. Check your address for the survey at your boundary.
What this means for growing in Big Stone County
Each reading below is measured for Big Stone County itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Drainage
MeasuredThe dominant soils across Big Stone County are moderately well drained, in hydrologic group C/D — roughly the middle of the drainage range.
This is close to the middle most vegetables prefer: it holds enough water to carry a crop between rains without staying waterlogged. The catch is that a wet spring or a low corner can still tip it soggy.
Plant on the site as-is for most crops, but keep the lowest, slowest-draining beds for moisture-tolerant plantings.
USDA NRCS SSURGO
Surface pH
MeasuredTopsoil across Big Stone County runs about pH 7.0–7.9, on the alkaline side.
Many vegetables cope, but acid-lovers like blueberries struggle, and iron and manganese lock up above about pH 7.5 — leaves yellow between the veins even in rich soil.
Elemental sulfur and generous organic matter lower pH slowly for the beds that need it; test first so you add only what the soil actually calls for.
USDA NRCS SSURGO
Wet ground
MeasuredAbout 30% of Big Stone County is mapped as hydric — wetland — soil.
If your lot falls in one of those pockets, a standard in-ground bed will fight waterlogging all season, and roots that need air will struggle.
Check how your own ground drains before you dig; raised beds or moisture-loving plantings turn a wet corner from a problem into a niche.
USDA NRCS SSURGO
Season length
MeasuredBig Stone County runs about 172 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
The kind of country Big Stone County is in
Big Stone County sits in the Northern Glaciated Plains — EPA Level III, inside the wider Great Plains. One consistent ecological setting across the whole county.
What Grows in Big Stone County
We scored all 1,086 plants against Big Stone County's own USDA zone 4b and its own 172-day season between hard freezes, using the same matching engine that runs a full parcel report. These cleared both. Sun, soil pH and drainage vary lot by lot — those are the parcel questions below. Each card opens that plant's Minnesota profile.
Is it too late to plant in Big Stone County?
For most of the year, no — what changes is which crops still fit the days remaining. Cool-season crops can go in from around Mar 24; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 21 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 10 — 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.
Documented around Big Stone County
- monarch butterfly3 documented records
Sighting records, so they follow observers as much as insects.
What gets applied to farmland in Big Stone County
USGS estimates 189,874 lb of Glyphosate on Big Stone County farmland in 2019, its largest by weight, ahead of Acetochlor (65,274 lb) and Metolachlor & Metolachlor-s (50,493 lb).
Farmland across the whole county, not any one lot. Check your address for the site-by-site record.
Safe to Grow Here?
What the federal record shows across Big Stone County — and how to grow with it.
We checked the federal record across Big Stone County — 123 documented sites across 6 of the 9 source types we track.
The most significant on record: 1 Toxics Release Inventory facility. Active industrial facilities reporting chemical releases to air, water, and land.
The federal record across Big Stone County is a modest one — a typical footprint for a growing area. Nothing here calls for alarm; it's worth knowing which recorded sites sit closest to where you grow, and each one on the map carries its type and location. If one turns out to be a near neighbor, a one-time soil test settles the question.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
What's on the federal record near Big Stone County
Closest first, across Big Stone County. Listing isn't leaking, and distance isn't exposure.
- 444445Nitrate · 1.0 mi
- BIG STONE AG SERVICE LLCBrownfields · 2.5 mi
- 566888Nitrate · 2.7 mi
- PRAIRIE PRIDE OF BIG STONECAFO · 2.7 mi
- Dicks StandardUnderground Storage Tanks · 3.1 mi
- Big Stone Coop-amoco Bulk PlantUnderground Storage Tanks · 3.1 mi
- Dac (daily Activity Center)Underground Storage Tanks · 3.1 mi
- Cenex Bulk PlantUnderground Storage Tanks · 3.1 mi
- Jamers 1 StopUnderground Storage Tanks · 3.2 mi
- Formerly Cherry StoreUnderground Storage Tanks · 3.2 mi
- Ortonville Waste Water PlantUnderground Storage Tanks · 3.6 mi
- Bitunimous Paving IncUnderground Storage Tanks · 3.6 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Big Stone County'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 Big Stone County.
Total Sites
123
across Big Stone County
Risk Level
Moderate
Highest-severity
1 Toxics Release Inventory facility
Sources Checked
across Big Stone County
Severity Distribution
across Big Stone County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Big Stone County, two things run higher than the national average across Big Stone County — CAFO (5 sites) and Nitrate (48 sites). That's not a problem with your land — it's information about it.
CAFO: CAFOs pose a different contamination profile than chemical sources.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Wash all produce consumed raw thoroughly, especially leafy greens grown near CAFOs.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in Big Stone County
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 Big Stone County average
Your land is one point inside Big Stone County
Everything above resolves to Big Stone County as a whole — one PHZM band and one county frost record, read across 319K 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 county 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 county average.
Your Lot vs the Big Stone County Average
Big Stone County Average
- ●USDA Zones 4b, averaged across Big Stone County
- ●One soil character for all of Big Stone County
- ●Frost dates read at Big Stone County's scale: Apr 21 to Oct 10
YOUR Parcel
- ✓Your exact zone, not Big Stone County's 4b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Big Stone County
Pull a site-specific report for your exact address in Big Stone County, Minnesota — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Big Stone County averages can't show:
We read public map data around Big Stone County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Big Stone County average
How we know this about Big Stone County
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at county grain; hard-freeze dates from NOAA 1991–2020 28°F normals at this county’s own record where one resolves, and the labelled statewide window where none does; soils from the USDA NRCS SSURGO survey, area-weighted across the county’s own map units; boundaries and acreage from US Census TIGER/Line 2025; the contamination and pesticide records from the federal sources named in their beats above. Where Big Stone County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Big Stone County
When does frost risk typically end in Big Stone County?
The last hard freeze (28°F) in Big Stone County typically lands around Apr 21, 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 12.
How long is the growing season in Big Stone County?
Measured between 28°F hard freezes, Big Stone County sees about 172 frost-free days — roughly Apr 21 through Oct 10, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 12 to Sep 26, about 137 days.
Is the soil safe to grow vegetables in Big Stone County?
The federal record around Big Stone County shows 123 documented sites, mostly Nitrate entries (48), the nearest Nitrate record about 1.0 miles out — a typical footprint for a growing area, and proximity to a documented site is information, not a diagnosis of any one yard. It's worth seeing which recorded sites sit closest to where you grow, and testing the soil before new food beds near any of them.
Everything above is measured at Big Stone County's scale — its 4b band and its 172-day season. Your yard writes its own version of Big Stone County's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
Will It Grow Here?
Zone fit is the first question — each answer below reads Minnesota's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at Big Stone County’s own scale
9 of the readings below were taken at Big Stone County's own scale — its own ~172-day span between 28°F freezes, the 3 most extensive soil series mapped here and 123 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Big Stone County's own USDA hardiness band, zones 4bUSDA PHZM 2023
- Big Stone County's own 28°F hard-freeze dates and its ~172-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Big Stone CountyUSDA NRCS SSURGO
- 123 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Nitrate record about 1.0 miles outFederal environmental registers
- Big Stone County's boundary and the 319,442 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 4b and a ~172-day seasonGrowable Ground crop-matching engine
- Big Stone County sitting wholly inside the Northern Glaciated PlainsUS EPA Level III Ecoregions
- Open occurrence records documented in Big Stone County for a tracked speciesGBIF derived datasets (CC0 / CC BY 4.0)
- Which agricultural compounds go onto Big Stone County farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every Minnesota grower plans around — written at state scale, so they stay on the state guidefrom Minnesota
What this page can’t tell you
- How the season shifts across Big Stone County — the ~172 days above is one reading at its centre; the 12 towns below each carry their owntowns in this county →
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Big Stone County's 319,442 acreswhy one lot differs from the next →
- Which of those 123 documented sites actually reaches your soil — that needs your address, the wind, and the groundwater directionhow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — none of it survives being averaged over Big Stone Countyread your own land →