Waterloo, Wisconsin, sits in USDA hardiness zone 5b — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
On paper, cabbage, cranberry, lavender, and collard greens all suit these conditions — on the ground, soil, sun, and drainage make the final call.
Even in Waterloo, 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 Waterloo 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 Waterloo — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Waterloo — the short answer
Waterloo, Wisconsin: USDA zone 5b, about 192 days between hard freezes, across 2K acres of city.
- USDA zone
- 5b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 12
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 21
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~192
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 2K 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 Waterloo's average, not your lot's — a low corner or a tree line moves it. Against Waterloo's 192-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Waterloo
Each reading below is measured for Waterloo itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredWaterloo runs about 192 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
MeasuredWaterloo 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 Waterloo is in
Waterloo sits in the Southeastern Wisconsin Till Plains — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Waterloo's own centroid rather than borrowed from Jefferson County.
What Grows in Waterloo
Every plant below cleared Waterloo's own zone 5b and its 192-day season. Each card opens that plant's Wisconsin profile. How we score.
Is it too late to plant in Waterloo?
Too late for some crops, right on time for others — a growing season is a sequence, not a deadline. Cool-season crops can go in from around Mar 15; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 12 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 21 — long-season crops need about 90 days of runway, quick greens only 30. The tail of the season still works: sixty-day crops into late summer, quick greens after, garlic last of all.
Documented around Waterloo
Spotted lanternfly documented 29 miles from Waterloo, first recorded 2023. What to watch for.
What's on the federal record near Waterloo
Closest first, within ~10 miles of Waterloo. Listing isn't leaking, and distance isn't exposure.
- JOHN MEITNERUnderground Storage Tanks · 100 ft
- JOEL WEBERUnderground Storage Tanks · 100 ft
- STEVE WEBERUnderground Storage Tanks · 100 ft
- TOWN OF YORKUnderground Storage Tanks · 100 ft
- JERRY HELLENBRAND IMP INCUnderground Storage Tanks · 100 ft
- CITY OF WATERLOOUnderground Storage Tanks · 150 ft
- U SERVE U SAVEUnderground Storage Tanks · 200 ft
- FURNITURE RESTORATION PRODUCTS LTDToxics Release Inventory · 250 ft
- JAMES GAUTHIER PROPERTIES/MINUTEMAN INCBrownfields · 300 ft
- FORMER GEHLER CHEVROLETUnderground Storage Tanks · 400 ft
- CENTURY 21 REALTYUnderground Storage Tanks · 500 ft
- LICKITY SPLITSUnderground Storage Tanks · 500 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Waterloo'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 Waterloo.
Total Sites
273
within ~10 miles of Waterloo
Risk Level
Elevated
Highest-severity
2 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Waterloo
Severity Distribution
within ~10 miles of Waterloo
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Waterloo, two things run higher than the national average within ~10 miles of Waterloo — CAFO (6 sites) and PFAS (3 sites). That's not a problem with your land — it's information about it.
CAFO: CAFOs pose a different contamination profile than chemical sources.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Wash all produce consumed raw thoroughly, especially leafy greens grown near CAFOs.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Check your specific parcel in Waterloo
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 Waterloo average
Your land is one point inside Waterloo
Everything above resolves to Waterloo as a whole — one PHZM band and one 28°F frost record, read across 2K 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 Waterloo Average
Waterloo Average
- ●USDA Zones 5b, averaged across Waterloo
- ●One soil character for all of Waterloo
- ●Frost dates read at Waterloo's scale: Apr 12 to Oct 21
YOUR Parcel
- ✓Your exact zone, not Waterloo's 5b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Waterloo
Pull a site-specific report for your exact address in Waterloo, Wisconsin — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Waterloo averages can't show:
We read public map data around Waterloo — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Waterloo average
How we know this about Waterloo
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 Waterloo’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 Waterloo
When does frost risk typically end in Waterloo?
The last hard freeze (28°F) in Waterloo typically lands around Apr 12, 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 3.
When is the first frost in Waterloo?
The first hard freeze (28°F) in Waterloo typically arrives around Oct 21, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 7, so the watching starts about Sep 21 — about 192 days after the spring freeze cleared.
How long is the growing season in Waterloo?
Measured between 28°F hard freezes, Waterloo sees about 192 frost-free days — roughly Apr 12 through Oct 21, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 3 to Oct 7, about 157 days.
Is the soil safe to grow vegetables in Waterloo?
The federal record around Waterloo is a meaningful one — 273 documented sites, mostly Underground Storage Tanks entries (157), the nearest Underground Storage Tanks record under a tenth of a mile 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 Waterloo?
From about Sep 21 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 21 (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 21. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Waterloo's scale — its 5b band and its 192-day season. Your yard writes its own version of Waterloo'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 Waterloo’s own scale
7 of the readings below were taken at Waterloo's own scale — its own ~192-day season between 28°F freezes, the 2,428 acres it covers and 273 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Waterloo's own USDA hardiness band, zones 5bUSDA PHZM 2023
- Waterloo's own 28°F hard-freeze dates, about Apr 12 and Oct 21 and the ~192-day span between themNOAA 1991–2020 Climate Normals
- 273 documented contamination sites on the federal record near Waterloo, the closest Underground Storage Tanks record under a tenth of a mile out from the town centreFederal environmental registers
- Waterloo's boundary and the 2,428 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5b and a ~192-day seasonGrowable Ground crop-matching engine
- The ecoregion at Waterloo's own centroid, the Southeastern Wisconsin Till PlainsUS EPA Level III Ecoregions
- A documented spotted-lanternfly record within reach of Waterloolydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so Waterloo's 2,428 acres read through its county's SSURGO summaryfrom Jefferson County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Jefferson 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 Jefferson County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Waterloo's 2,428 acreswhy one lot differs from the next →
- Which side of Waterloo you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 2,428 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record under a tenth of a mile 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 Waterloo-wide figureread your own land →
More in Wisconsin
Wider growing context
What grows across WisconsinWaterloo sits outside our named growing regions, so Wisconsin as a whole is its closest context here.
Nearby growing guides