Keosauqua, 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.
Among the crops suited to this profile: cabbage, blueberry, lavender, and collard greens. The site-level story — soil, sun, drainage — decides the rest.
Even in Keosauqua, 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 Keosauqua 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 Keosauqua — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Keosauqua — the short answer
Keosauqua, Iowa: USDA zone 5b, about 210 days between hard freezes, across 934 acres of city.
- USDA zone
- 5b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 4
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 31
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~210
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 934 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 Keosauqua's average, not your lot's — a low corner or a tree line moves it. Against Keosauqua's 210-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Keosauqua
Each reading below is measured for Keosauqua itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredKeosauqua runs about 210 days between hard freezes — a long growing season.
There is slack for succession plantings and slow-finishing crops: many vegetables can be sown twice, and the heat-lovers have time to ripen fully.
Plan a second sowing of quick crops after the first comes out, and use the fall window most gardeners let sit idle.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredKeosauqua 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 Keosauqua is in
Keosauqua sits in the Central Irregular Plains — EPA Level III, inside the wider Great Plains. That is read at Keosauqua's own centroid rather than borrowed from Van Buren County.
What Grows in Keosauqua
Every plant below cleared Keosauqua's own zone 5b and its 210-day season. Each card opens that plant's Iowa profile. How we score.
Is it too late to plant in Keosauqua?
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 7; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 4 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 31 — long-season crops need about 90 days of runway, quick greens only 30. A long window like this one runs successions deep into fall — and even its last weeks take quick greens and garlic.
What's on the federal record near Keosauqua
Closest first, within ~10 miles of Keosauqua. Listing isn't leaking, and distance isn't exposure.
- 069N10W36BDBA 03723 1949Keosauqua 2Nitrate · 350 ft
- 069N10W36CAA 1932Keosauqua 1Nitrate · 850 ft
- BENS SERVICEUnderground Storage Tanks · 1000 ft
- IA DEPT OF TRANSPORTATIONUnderground Storage Tanks · 1000 ft
- VAN BUREN COUNTY SHERIFFS DEPTUnderground Storage Tanks · 1000 ft
- HILLPHOENIX SPECIALTY PRODUCTSToxics Release Inventory · 1600 ft
- HILLPHOENIX SPECIALTY PRODUCTSBrownfields · 1600 ft
- KEOSAUQUA MOTOR COUnderground Storage Tanks · 1600 ft
- 069N10W36ADANitrate · 1600 ft
- VAN BUREN COUNTY CONSERVATION BOARDUnderground Storage Tanks · 1600 ft
- POWELL STATIONUnderground Storage Tanks · 1700 ft
- MJD SALES & SERVICEBrownfields · 1700 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Keosauqua'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 Keosauqua.
Total Sites
75
within ~10 miles of Keosauqua
Risk Level
Moderate
Highest-severity
1 Toxics Release Inventory facility
Sources Checked
within ~10 miles of Keosauqua
Severity Distribution
within ~10 miles of Keosauqua
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Keosauqua, Nitrate runs higher than the national average — 40 sites within ~10 miles of Keosauqua. It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in Keosauqua
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 Keosauqua average
Your land is one point inside Keosauqua
Everything above resolves to Keosauqua as a whole — one PHZM band and one 28°F frost record, read across 934 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 Keosauqua Average
Keosauqua Average
- ●USDA Zones 5b, averaged across Keosauqua
- ●One soil character for all of Keosauqua
- ●Frost dates read at Keosauqua's scale: Apr 4 to Oct 31
YOUR Parcel
- ✓Your exact zone, not Keosauqua's 5b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Keosauqua
Pull a site-specific report for your exact address in Keosauqua, Iowa — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Keosauqua averages can't show:
We read public map data around Keosauqua — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Keosauqua average
How we know this about Keosauqua
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 Keosauqua’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 Keosauqua
When does frost risk typically end in Keosauqua?
The last hard freeze (28°F) in Keosauqua typically lands around Apr 4, 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 Apr 25.
When is the first frost in Keosauqua?
The first hard freeze (28°F) in Keosauqua typically arrives around Oct 31, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 17, so the watching starts about Oct 1 — about 210 days after the spring freeze cleared.
How long is the growing season in Keosauqua?
Measured between 28°F hard freezes, Keosauqua sees about 210 frost-free days — roughly Apr 4 through Oct 31, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 25 to Oct 17, about 175 days.
Is the soil safe to grow vegetables in Keosauqua?
The federal record around Keosauqua shows 75 documented sites, mostly Nitrate entries (40), the nearest Nitrate record under a tenth of a mile 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 Keosauqua?
From about Oct 1 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 31 (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 31. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Keosauqua's scale — its 5b band and its 210-day season. Your yard writes its own version of Keosauqua'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 Keosauqua’s own scale
6 of the readings below were taken at Keosauqua's own scale — its own ~210-day season between 28°F freezes, the 934 acres it covers and 75 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Keosauqua's own USDA hardiness band, zones 5bUSDA PHZM 2023
- Keosauqua's own 28°F hard-freeze dates, about Apr 4 and Oct 31 and the ~210-day span between themNOAA 1991–2020 Climate Normals
- 75 documented contamination sites on the federal record near Keosauqua, the closest Nitrate record under a tenth of a mile out from the town centreFederal environmental registers
- Keosauqua's boundary and the 934 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5b and a ~210-day seasonGrowable Ground crop-matching engine
- The ecoregion at Keosauqua's own centroid, the Central Irregular PlainsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Keosauqua's 934 acres read through its county's SSURGO summaryfrom Van Buren County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Van Buren 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 Van Buren County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Keosauqua's 934 acreswhy one lot differs from the next →
- Which side of Keosauqua you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 934 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Nitrate 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 Keosauqua-wide figureread your own land →