Montezuma, Iowa, sits in USDA hardiness zone 5b — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
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 Montezuma, 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 Montezuma 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 Montezuma — soil, climate, flood, and parcel records. How we handle your address.
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Montezuma — the short answer
Montezuma, Iowa: USDA zone 5b, about 193 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 22
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~193
- 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 Montezuma's average, not your lot's — a low corner or a tree line moves it. Against Montezuma's 193-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Montezuma
Each reading below is measured for Montezuma itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredMontezuma runs about 193 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
MeasuredMontezuma 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 Montezuma is in
Montezuma sits in the Western Corn Belt Plains — EPA Level III, inside the wider Great Plains. That is read at Montezuma's own centroid rather than borrowed from Poweshiek County.
What Grows in Montezuma
Every plant below cleared Montezuma's own zone 5b and its 193-day season. Each card opens that plant's Iowa profile. How we score.
Is it too late to plant in Montezuma?
Usually not — gardeners here simply switch what goes in the ground as the season moves. 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 22 — 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 Montezuma
Closest first, within ~10 miles of Montezuma. Listing isn't leaking, and distance isn't exposure.
- DAVID CARTERUnderground Storage Tanks · 800 ft
- THE DEPOT MONTEZUMA LLCUnderground Storage Tanks · 850 ft
- FARM SERVICEUnderground Storage Tanks · 900 ft
- WIDMER REPAIR SERVICEUnderground Storage Tanks · 1000 ft
- POWESHIEK COUNTY GUERNSEY SHOPUnderground Storage Tanks · 1100 ft
- PONDEROSA MARINAUnderground Storage Tanks · 1100 ft
- R&R RESTORATION AUTOBrownfields · 1100 ft
- CASEYS GENERAL STORE 3309Underground Storage Tanks · 1100 ft
- VANNOY CHEVROLET CO INCBrownfields · 1300 ft
- GLENS TRACTOR REPAIR INCBrownfields · 1500 ft
- Not KnownUnderground Storage Tanks · 1700 ft
- MUNICIPAL LIGHT & POWERUnderground Storage Tanks · 1700 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Montezuma'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 Montezuma.
Total Sites
61
within ~10 miles of Montezuma
Risk Level
Moderate
Highest-severity
3 Toxics Release Inventory facilities
Sources Checked
within ~10 miles of Montezuma
Severity Distribution
within ~10 miles of Montezuma
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 Montezuma
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 Montezuma average
Your land is one point inside Montezuma
Everything above resolves to Montezuma 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 Montezuma Average
Montezuma Average
- ●USDA Zones 5b, averaged across Montezuma
- ●One soil character for all of Montezuma
- ●Frost dates read at Montezuma's scale: Apr 12 to Oct 22
YOUR Parcel
- ✓Your exact zone, not Montezuma's 5b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Montezuma
Pull a site-specific report for your exact address in Montezuma, Iowa — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Montezuma averages can't show:
We read public map data around Montezuma — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Montezuma average
How we know this about Montezuma
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 Montezuma’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 Montezuma
When does frost risk typically end in Montezuma?
The last hard freeze (28°F) in Montezuma 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 Montezuma?
The first hard freeze (28°F) in Montezuma typically arrives around Oct 22, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 8, so the watching starts about Sep 22 — about 193 days after the spring freeze cleared.
How long is the growing season in Montezuma?
Measured between 28°F hard freezes, Montezuma sees about 193 frost-free days — roughly Apr 12 through Oct 22, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 3 to Oct 8, about 158 days.
Is the soil safe to grow vegetables in Montezuma?
The federal record around Montezuma shows 61 documented sites, mostly Underground Storage Tanks entries (34), the nearest Underground Storage Tanks record about 0.2 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.
How do I protect my plants from frost in Montezuma?
From about Sep 22 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 22 (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 22. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Montezuma's scale — its 5b band and its 193-day season. Your yard writes its own version of Montezuma'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 Montezuma’s own scale
6 of the readings below were taken at Montezuma's own scale — its own ~193-day season between 28°F freezes, the 1,581 acres it covers and 61 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Montezuma's own USDA hardiness band, zones 5bUSDA PHZM 2023
- Montezuma's own 28°F hard-freeze dates, about Apr 12 and Oct 22 and the ~193-day span between themNOAA 1991–2020 Climate Normals
- 61 documented contamination sites on the federal record near Montezuma, the closest Underground Storage Tanks record about 0.2 miles out from the town centreFederal environmental registers
- Montezuma's boundary and the 1,581 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5b and a ~193-day seasonGrowable Ground crop-matching engine
- The ecoregion at Montezuma's own centroid, the Western Corn Belt PlainsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Montezuma's 1,581 acres read through its county's SSURGO summaryfrom Poweshiek County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Poweshiek County
- The growing challenges every Iowa grower plans around — written at state scale, so they stay on the state guidefrom Iowa
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Poweshiek County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Montezuma's 1,581 acreswhy one lot differs from the next →
- Which side of Montezuma you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 1,581 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.2 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 Montezuma-wide figureread your own land →
More in Iowa
Wider growing context
What grows across IowaMontezuma sits outside our named growing regions, so Iowa as a whole is its closest context here.
Nearby growing guides