Glenwood, Iowa, sits in USDA hardiness zone 5b — a zone band wide enough that plant choice, not possibility, is the interesting question.
The conditions favor cabbage, cranberry, lavender, and collard greens, among others — though every individual site edits that list with its own soil, sun, and drainage.
Even in Glenwood, 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 Glenwood 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 Glenwood — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Glenwood — the short answer
Glenwood, Iowa: USDA zone 5b, about 204 days between hard freezes, across 2K acres of city.
- USDA zone
- 5b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 6
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 27
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~204
- 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 Glenwood's average, not your lot's — a low corner or a tree line moves it. Against Glenwood's 204-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Glenwood
Each reading below is measured for Glenwood itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredGlenwood runs about 204 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
MeasuredGlenwood 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 Glenwood is in
Glenwood sits in the Western Corn Belt Plains — EPA Level III, inside the wider Great Plains. That is read at Glenwood's own centroid rather than borrowed from Mills County.
What Grows in Glenwood
Every plant below cleared Glenwood's own zone 5b and its 204-day season. Each card opens that plant's Iowa profile. How we score.
Is it too late to plant in Glenwood?
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 9; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 6 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 27 — long-season crops need about 90 days of runway, quick greens only 30. There is slack in a calendar like this — late plantings, second rounds of favorites, and a fall bench that keeps beds working.
What's on the federal record near Glenwood
Closest first, within ~10 miles of Glenwood. Listing isn't leaking, and distance isn't exposure.
- GLENWOOD TRANSIT LINE INCUnderground Storage Tanks · 100 ft
- ROSSLYN PROPERTYUnderground Storage Tanks · 600 ft
- RINGS PROFESSIONAL CLEANERBrownfields · 650 ft
- FORMER BOLDRA''S SERVICEUnderground Storage Tanks · 850 ft
- BILL NISSEN FORD INCUnderground Storage Tanks · 1100 ft
- LINCOLN FARM & HOMEUnderground Storage Tanks · 1200 ft
- CITY OF GLENWOODUnderground Storage Tanks · 1200 ft
- UNITOG RENTAL SERVICEUnderground Storage Tanks · 1300 ft
- WHITE OAK STATION 57Underground Storage Tanks · 1300 ft
- FORMER JACOBSON''S TEXACOUnderground Storage Tanks · 1300 ft
- GASKILL OIL COUnderground Storage Tanks · 1500 ft
- CASEY''S GENERAL STORE 1500Underground Storage Tanks · 1600 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Glenwood'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 Glenwood.
Sources Checked
within ~10 miles of Glenwood
Severity Distribution
within ~10 miles of Glenwood
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Glenwood, Toxics Release Inventory runs higher than the national average — 16 sites within ~10 miles of Glenwood. That's not a problem with your land — it's information about it.
Toxics Release Inventory: TRI facilities report annual chemical releases to air, water, and land.
Check prevailing wind direction — downwind parcels face higher exposure than upwind or crosswind locations.
Check your specific parcel in Glenwood
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 Glenwood average
Your land is one point inside Glenwood
Everything above resolves to Glenwood 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 Glenwood Average
Glenwood Average
- ●USDA Zones 5b, averaged across Glenwood
- ●One soil character for all of Glenwood
- ●Frost dates read at Glenwood's scale: Apr 6 to Oct 27
YOUR Parcel
- ✓Your exact zone, not Glenwood's 5b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Glenwood
Pull a site-specific report for your exact address in Glenwood, Iowa — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Glenwood averages can't show:
We read public map data around Glenwood — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Glenwood average
How we know this about Glenwood
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 Glenwood’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 Glenwood
When does frost risk typically end in Glenwood?
The last hard freeze (28°F) in Glenwood typically lands around Apr 6, 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 27.
When is the first frost in Glenwood?
The first hard freeze (28°F) in Glenwood typically arrives around Oct 27, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 13, so the watching starts about Sep 27 — about 204 days after the spring freeze cleared.
How long is the growing season in Glenwood?
Measured between 28°F hard freezes, Glenwood sees about 204 frost-free days — roughly Apr 6 through Oct 27, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 27 to Oct 13, about 169 days.
Is the soil safe to grow vegetables in Glenwood?
The federal record around Glenwood is a meaningful one — 140 documented sites, mostly Underground Storage Tanks entries (66), 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 Glenwood?
From about Sep 27 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 27 (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 27. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Glenwood's scale — its 5b band and its 204-day season. Your yard writes its own version of Glenwood'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 Glenwood’s own scale
6 of the readings below were taken at Glenwood's own scale — its own ~204-day season between 28°F freezes, the 1,871 acres it covers and 140 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Glenwood's own USDA hardiness band, zones 5bUSDA PHZM 2023
- Glenwood's own 28°F hard-freeze dates, about Apr 6 and Oct 27 and the ~204-day span between themNOAA 1991–2020 Climate Normals
- 140 documented contamination sites on the federal record near Glenwood, the closest Underground Storage Tanks record under a tenth of a mile out from the town centreFederal environmental registers
- Glenwood's boundary and the 1,871 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5b and a ~204-day seasonGrowable Ground crop-matching engine
- The ecoregion at Glenwood'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 Glenwood's 1,871 acres read through its county's SSURGO summaryfrom Mills County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Mills 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 Mills County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Glenwood's 1,871 acreswhy one lot differs from the next →
- Which side of Glenwood you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 1,871 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 Glenwood-wide figureread your own land →
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