Fitchburg, Wisconsin, sits in USDA hardiness zone 5b — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
A short list that earns its place here — cabbage, cranberry, lavender, and collard greens — with any one site's soil, sun, and drainage making the final cut.
Even in Fitchburg, 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 Fitchburg 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 Fitchburg — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Fitchburg — the short answer
Fitchburg, Wisconsin: USDA zone 5b, about 182 days between hard freezes, across 23K acres of city.
- USDA zone
- 5b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 19
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 18
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~182
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 23K 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 5b is Fitchburg's average, not your lot's — a low corner or a tree line moves it. Against Fitchburg's 182-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Fitchburg
Each reading below is measured for Fitchburg itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredFitchburg runs about 182 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
MeasuredFitchburg sits in USDA hardiness zone 5b.
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 Fitchburg is in
Fitchburg sits in the Southeastern Wisconsin Till Plains — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Fitchburg's own centroid rather than borrowed from Dane County.
What Grows in Fitchburg
Every plant below cleared Fitchburg's own zone 5b and its 182-day season. Each card opens that plant's Wisconsin profile. How we score.
Is it too late to plant in Fitchburg?
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 22; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 19 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 18 — long-season crops need about 90 days of runway, quick greens only 30. As the window narrows, the plantings just get faster — fall brassicas, then greens, then garlic to finish.
What's on the federal record near Fitchburg
Closest first, within ~10 miles of Fitchburg. Listing isn't leaking, and distance isn't exposure.
- FERGUSON WATERWORKS #2520Brownfields · 550 ft
- City Of FitchburgUnderground Storage Tanks · 1400 ft
- NILES SCHLEYUnderground Storage Tanks · 1900 ft
- ENCOMPASS HEALTH REHABILITATION HOSPITAL OF FITCHBURGBrownfields · 0.6 mi
- TEAM MADISON DATA CENTERToxics Release Inventory · 0.7 mi
- PROMEGA CORP - 5500 NOBELBrownfields · 0.7 mi
- BELLBROOK LABS LLCBrownfields · 0.7 mi
- WIBA RADIOUnderground Storage Tanks · 0.9 mi
- MERITER FITCHBURG CLINICBrownfields · 1.0 mi
- RICHARDSON BUS SERVICEUnderground Storage Tanks · 1.2 mi
- Biopharmaceutical Technology CenterUnderground Storage Tanks · 1.4 mi
- PROMEGA CORP - BIOPHARMACEUTICAL TECH CTRBrownfields · 1.4 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Fitchburg'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 Fitchburg.
Sources Checked
within ~10 miles of Fitchburg
Severity Distribution
within ~10 miles of Fitchburg
Highest-Severity Sites
Know Before You Grow
- •Underground tanks leak petroleum as they age — near a former filling station, test the soil.
- •Near a brownfield, raised beds of imported soil give your food clean ground.
- •On a private well, test for nitrates: above 10 mg/L the water needs treatment before irrigating.
Check your specific parcel in Fitchburg
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 Fitchburg average
Your land is one point inside Fitchburg
Everything above resolves to Fitchburg as a whole — one PHZM band and one 28°F frost record, read across 23K 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 city 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 Fitchburg Average
Fitchburg Average
- ●USDA Zones 5b, averaged across Fitchburg
- ●One soil character for all of Fitchburg
- ●Frost dates read at Fitchburg's scale: Apr 19 to Oct 18
YOUR Parcel
- ✓Your exact zone, not Fitchburg's 5b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Fitchburg
Pull a site-specific report for your exact address in Fitchburg, Wisconsin — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Fitchburg averages can't show:
We read public map data around Fitchburg — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Fitchburg average
How we know this about Fitchburg
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this city’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Fitchburg’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 city grain anywhere on this page — there is no city-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 Fitchburg
When does frost risk typically end in Fitchburg?
The last hard freeze (28°F) in Fitchburg typically lands around Apr 19, 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 10.
When is the first frost in Fitchburg?
The first hard freeze (28°F) in Fitchburg typically arrives around Oct 18, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 4, so the watching starts about Sep 18 — about 182 days after the spring freeze cleared.
How long is the growing season in Fitchburg?
Measured between 28°F hard freezes, Fitchburg sees about 182 frost-free days — roughly Apr 19 through Oct 18, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 10 to Oct 4, about 147 days.
Is the soil safe to grow vegetables in Fitchburg?
The federal record around Fitchburg is a meaningful one — 1,799 documented sites, mostly Underground Storage Tanks entries (1,060), the nearest Brownfields record about 0.1 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 Fitchburg?
From about Sep 18 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 18 (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 18. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Fitchburg's scale — its 5b band and its 182-day season. Your yard writes its own version of Fitchburg'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 Fitchburg’s own scale
6 of the readings below were taken at Fitchburg's own scale — its own ~182-day season between 28°F freezes, the 22,535 acres it covers and 1,799 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Fitchburg's own USDA hardiness band, zones 5bUSDA PHZM 2023
- Fitchburg's own 28°F hard-freeze dates, about Apr 19 and Oct 18 and the ~182-day span between themNOAA 1991–2020 Climate Normals
- 1,799 documented contamination sites on the federal record near Fitchburg, the closest Brownfields record about 0.1 miles out from the town centreFederal environmental registers
- Fitchburg's boundary and the 22,535 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5b and a ~182-day seasonGrowable Ground crop-matching engine
- The ecoregion at Fitchburg's own centroid, the Southeastern Wisconsin Till PlainsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Fitchburg's 22,535 acres read through its county's SSURGO summaryfrom Dane County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Dane County
- The growing challenges every Wisconsin grower plans around — written at state scale, so they stay on the state guidefrom Wisconsin
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Dane County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Fitchburg's 22,535 acreswhy one lot differs from the next →
- Which side of Fitchburg you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 22,535 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields record about 0.1 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 Fitchburg-wide figureread your own land →
More in Wisconsin
Wider growing context
What grows across WisconsinFitchburg sits outside our named growing regions, so Wisconsin as a whole is its closest context here.
Nearby growing guides