Fillmore County, in Minnesota, 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.
Fillmore County lies within the Driftless Area — a regional growing area with its own character.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Fillmore County holds more than one microclimate.
Soils and elevations shift across Fillmore 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 Fillmore County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Fillmore County — the short answer
Fillmore County, Minnesota: USDA zone 4b, about 166 days between hard freezes, across 551K acres.
- USDA zone
- 4b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 27
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Oct 10
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~166
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 551K 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 Fillmore County's average, not your lot's — a low corner or a tree line moves it. Against Fillmore County's 166-day season, see what your own ground reads.
Heat in Fillmore County
Across a year, Fillmore County accumulates about 2,290 growing degree days above 50°F, about 25 more than the middle Minnesota county — ahead of 46 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 Fillmore County
Across Fillmore County, the ground is predominantly Alfisols, where Fayette, Downs, and Tama are the most extensive named soil series. The soil is generally well drained with a silt loam surface. Topsoil pH runs about 6.2–6.5, slightly acidic. Rainfall drains through hydrologic group C soils.
Soil order
Alfisols
Drainage
Well drained
Prime farmland
48%
Hydric soils
8%
Soil still varies lot by lot — soil types explained.
How the ground varies across Fillmore County
The USDA soil survey maps 79% of Fillmore County as well drained — but another 21% drains differently: 11% moderately well drained, 7% poorly drained.
Fayette is the most extensive named soil at 33% of mapped acres, then Downs (9%) and Tama (9%).
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 Fillmore County
Each reading below is measured for Fillmore 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 Fillmore County are well drained, in hydrologic group C — ground that drains quickly.
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
MeasuredTopsoil across Fillmore County runs about pH 6.2–6.5, close to neutral.
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
Season length
MeasuredFillmore County runs about 166 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
MeasuredFillmore County 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 Fillmore County is in
Fillmore County spans 2 EPA Level III ecoregions — Driftless Area (93%) and Western Corn Belt Plains (7%). Which one your land falls in changes what grows wild there and how the ground behaves, and a county-wide answer cannot tell you which.
What Grows in Fillmore County
We scored all 1,086 plants against Fillmore County's own USDA zone 4b and its own 166-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 Fillmore County?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Mar 30; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 27 (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. Even past midsummer there is room for a true fall garden here, and garlic planted near the close carries the momentum into next year.
Documented around Fillmore County
- Japanese beetle1 documented records
- monarch butterfly38 documented records
Sighting records, so they follow observers as much as insects.
What gets applied to farmland in Fillmore County
USGS estimates 263,670 lb of Glyphosate on Fillmore County farmland in 2019, its largest by weight, ahead of Acetochlor (149,400 lb) and Metolachlor & Metolachlor-s (90,928 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 Fillmore County — and how to grow with it.
We checked the federal record across Fillmore County — 379 documented sites across 6 of the 9 source types we track.
The most significant on record: 7 Toxics Release Inventory facilities. Active industrial facilities reporting chemical releases to air, water, and land.
There's a meaningful federal record across Fillmore County — worth a look before you plant food, not a reason to hold back from growing. Proximity to a documented site is information, not a diagnosis of any one yard. A soil test before new food beds is the sensible precaution here, and the map shows exactly which sites sit where, so you can see what's actually near you.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
What's on the federal record near Fillmore County
Closest first, across Fillmore County. Listing isn't leaking, and distance isn't exposure.
- GEHLING IMPLEMENTBrownfields · 850 ft
- MINNESOTA STATE VETERANS CEMETERY PRESTONBrownfields · 850 ft
- PRESTON VETERANS HOMEBrownfields · 1000 ft
- MDVA CENTRAL PHARMACY PRESTONBrownfields · 1000 ft
- FILLMORE COUNTY SHERIFF'S OFFICEBrownfields · 2500 ft
- FILLMORE COUNTYBrownfields · 2500 ft
- BAUER BUILT TIRE & SERVICEBrownfields · 2500 ft
- Fillmore County Highway DeptUnderground Storage Tanks · 2500 ft
- POET BIOREFINING - PRESTONBrownfields · 2600 ft
- POET BIOREFINING - PRESTONToxics Release Inventory · 2600 ft
- 103N10W31CCD 01 PrestonNitrate · 2600 ft
- Curts StandardUnderground Storage Tanks · 0.5 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Fillmore 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 Fillmore County.
Total Sites
379
across Fillmore County
Risk Level
Elevated
Highest-severity
7 Toxics Release Inventory facilities
Sources Checked
across Fillmore County
Severity Distribution
across Fillmore County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Fillmore County, two things run higher than the national average across Fillmore County — CAFO (9 sites) and Nitrate (168 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 Fillmore 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 Fillmore County average
Your land is one point inside Fillmore County
Everything above resolves to Fillmore County as a whole — one PHZM band and one county frost record, read across 551K 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 Fillmore County Average
Fillmore County Average
- ●USDA Zones 4b, averaged across Fillmore County
- ●One soil character for all of Fillmore County
- ●Frost dates read at Fillmore County's scale: Apr 27 to Oct 10
YOUR Parcel
- ✓Your exact zone, not Fillmore County's 4b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Fillmore County
Pull a site-specific report for your exact address in Fillmore County, Minnesota — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Fillmore County averages can't show:
We read public map data around Fillmore County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Fillmore County average
How we know this about Fillmore 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 Fillmore County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Fillmore County
When does frost risk typically end in Fillmore County?
The last hard freeze (28°F) in Fillmore County typically lands around Apr 27, 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 18.
How long is the growing season in Fillmore County?
Measured between 28°F hard freezes, Fillmore County sees about 166 frost-free days — roughly Apr 27 through Oct 10, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 18 to Sep 26, about 131 days.
Is the soil safe to grow vegetables in Fillmore County?
The federal record around Fillmore County is a meaningful one — 379 documented sites, mostly Nitrate entries (168), the nearest Brownfields record about 0.2 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.
Everything above is measured at Fillmore County's scale — its 4b band and its 166-day season. Your yard writes its own version of Fillmore 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 Fillmore County’s own scale
9 of the readings below were taken at Fillmore County's own scale — its own ~166-day span between 28°F freezes, the 3 most extensive soil series mapped here and 379 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Fillmore County's own USDA hardiness band, zones 4bUSDA PHZM 2023
- Fillmore County's own 28°F hard-freeze dates and its ~166-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Fillmore CountyUSDA NRCS SSURGO
- 379 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Brownfields record about 0.2 miles outFederal environmental registers
- Fillmore County's boundary and the 551,253 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 4b and a ~166-day seasonGrowable Ground crop-matching engine
- The 2 ecoregions Fillmore County spans, Driftless Area the largestUS EPA Level III Ecoregions
- Open occurrence records documented in Fillmore County for 2 tracked speciesGBIF derived datasets (CC0 / CC BY 4.0)
- Which agricultural compounds go onto Fillmore 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 Fillmore County — the ~166 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 Fillmore County's 551,253 acreswhy one lot differs from the next →
- Which of those 379 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 Fillmore Countyread your own land →