Columbus City, Iowa, sits in USDA hardiness zone 5b — a zone band wide enough that plant choice, not possibility, is the interesting question.
Growers here do well with cabbage, cranberry, lavender, and collard greens — with the usual caveat that any single yard's soil, sun, and drainage cast the deciding vote.
Even in Columbus City, 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 Columbus City 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 Columbus City — soil, climate, flood, and parcel records. How we handle your address.
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Columbus City — the short answer
Columbus City, Iowa: USDA zone 5b, about 200 days between hard freezes, across 154 acres of city.
- USDA zone
- 5b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 8
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 25
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~200
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 154 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 Columbus City's average, not your lot's — a low corner or a tree line moves it. Against Columbus City's 200-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Columbus City
Each reading below is measured for Columbus City itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredColumbus City runs about 200 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
MeasuredColumbus City 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 Columbus City is in
Columbus City sits in the Western Corn Belt Plains — EPA Level III, inside the wider Great Plains. That is read at Columbus City's own centroid, and it is not what its county reads: Louisa County is mostly Interior River Valleys and Hills. The wider page above you is answering a different question about different ground.
What Grows in Columbus City
Every plant below cleared Columbus City's own zone 5b and its 200-day season. Each card opens that plant's Iowa profile. How we score.
Is it too late to plant in Columbus City?
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 11; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 8 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 25 — 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 Columbus City
Closest first, within ~10 miles of Columbus City. Listing isn't leaking, and distance isn't exposure.
- HACIENDA BARUnderground Storage Tanks · 250 ft
- 075N05W19ADBB 19170 1966Columbus City 1Nitrate · 350 ft
- COLUMBUS COMMUNITY SCHOOLSUnderground Storage Tanks · 0.7 mi
- ITC MIDWEST COLUMBUS JUNCTIONBrownfields · 0.8 mi
- FORMER IDOT MAINTENANCE FACILITYUnderground Storage Tanks · 1.0 mi
- 074N04W06BCDNitrate · 1.2 mi
- L-W SERVICE COUnderground Storage Tanks · 1.4 mi
- NATURAL GAS PIPELINE CO OF AMERICAUnderground Storage Tanks · 1.4 mi
- 075N05W24CDDA 07957 1956Nitrate · 1.4 mi
- 075N05W26CDC 09779 1958Nitrate · 1.5 mi
- CECIL''S STANDARDUnderground Storage Tanks · 1.5 mi
- 075N04W19CCAB 38230 1935Columbus Junction NorthNitrate · 1.5 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Columbus City'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 Columbus City.
Total Sites
145
within ~10 miles of Columbus City
Risk Level
Moderate
Highest-severity
2 Toxics Release Inventory facilities
Sources Checked
within ~10 miles of Columbus City
Severity Distribution
within ~10 miles of Columbus City
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Columbus City, Nitrate runs higher than the national average — 88 sites within ~10 miles of Columbus City. Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
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 Columbus City
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 Columbus City average
Your land is one point inside Columbus City
Everything above resolves to Columbus City as a whole — one PHZM band and one 28°F frost record, read across 154 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 Columbus City Average
Columbus City Average
- ●USDA Zones 5b, averaged across Columbus City
- ●One soil character for all of Columbus City
- ●Frost dates read at Columbus City's scale: Apr 8 to Oct 25
YOUR Parcel
- ✓Your exact zone, not Columbus City's 5b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Columbus City
Pull a site-specific report for your exact address in Columbus City, Iowa — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Columbus City averages can't show:
We read public map data around Columbus City — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Columbus City average
How we know this about Columbus City
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 Columbus City’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 Columbus City
When does frost risk typically end in Columbus City?
The last hard freeze (28°F) in Columbus City typically lands around Apr 8, 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 29.
When is the first frost in Columbus City?
The first hard freeze (28°F) in Columbus City typically arrives around Oct 25, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 11, so the watching starts about Sep 25 — about 200 days after the spring freeze cleared.
How long is the growing season in Columbus City?
Measured between 28°F hard freezes, Columbus City sees about 200 frost-free days — roughly Apr 8 through Oct 25, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 29 to Oct 11, about 165 days.
Is the soil safe to grow vegetables in Columbus City?
The federal record around Columbus City shows 145 documented sites, mostly Nitrate entries (88), the nearest Underground Storage Tanks 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 Columbus City?
From about Sep 25 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 25 (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 25. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Columbus City's scale — its 5b band and its 200-day season. Your yard writes its own version of Columbus City'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 Columbus City’s own scale
6 of the readings below were taken at Columbus City's own scale — its own ~200-day season between 28°F freezes, the 154 acres it covers and 145 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Columbus City's own USDA hardiness band, zones 5bUSDA PHZM 2023
- Columbus City's own 28°F hard-freeze dates, about Apr 8 and Oct 25 and the ~200-day span between themNOAA 1991–2020 Climate Normals
- 145 documented contamination sites on the federal record near Columbus City, the closest Underground Storage Tanks record under a tenth of a mile out from the town centreFederal environmental registers
- Columbus City's boundary and the 154 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5b and a ~200-day seasonGrowable Ground crop-matching engine
- Columbus City sits in the Western Corn Belt Plains — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Columbus City's 154 acres read through its county's SSURGO summaryfrom Louisa County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Louisa 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 Louisa County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Columbus City's 154 acreswhy one lot differs from the next →
- Which side of Columbus City you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 154 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 Columbus City-wide figureread your own land →