Stanhope, Iowa, sits in USDA hardiness zone 5a — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
Reliable performers under these conditions include cabbage, cranberry, lavender, and collard greens; what your own ground favors still comes down to its soil, sun, and drainage.
Even in Stanhope, 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 Stanhope 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 Stanhope — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Stanhope — the short answer
Stanhope, Iowa: USDA zone 5a, about 189 days between hard freezes, across 627 acres of city.
- USDA zone
- 5a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 15
- 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
- ~189
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 627 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 5a is Stanhope's average, not your lot's — a low corner or a tree line moves it. Against Stanhope's 189-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Stanhope
Each reading below is measured for Stanhope itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredStanhope runs about 189 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
MeasuredStanhope sits in USDA hardiness zone 5a.
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 Stanhope is in
Stanhope sits in the Western Corn Belt Plains — EPA Level III, inside the wider Great Plains. That is read at Stanhope's own centroid rather than borrowed from Hamilton County.
What Grows in Stanhope
Every plant below cleared Stanhope's own zone 5a and its 189-day season. Each card opens that plant's Iowa profile. How we score.
Is it too late to plant in Stanhope?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Mar 18; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 15 (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. Even past midsummer there is room for a true fall garden here, and garlic planted near the close carries the momentum into next year.
What's on the federal record near Stanhope
Closest first, within ~10 miles of Stanhope. Listing isn't leaking, and distance isn't exposure.
- FORMER MIKES STANDARDUnderground Storage Tanks · 200 ft
- SPARKY''S ONE STOP #9Underground Storage Tanks · 300 ft
- FORMER HOVE TRUCKLINEUnderground Storage Tanks · 300 ft
- HILLS MAPLE CREST FARMSUnderground Storage Tanks · 350 ft
- GORDON HOVEUnderground Storage Tanks · 350 ft
- 086N25W05BCCC 00820 1938Stanhope 3Nitrate · 350 ft
- HAMILTON COUNTY MAINTENANCE SHEDUnderground Storage Tanks · 400 ft
- 086N25W05BCCB 1973Stanhope 5Nitrate · 500 ft
- CENTRAL IOWA COOPERATIVEUnderground Storage Tanks · 500 ft
- READ AUTO CO INCUnderground Storage Tanks · 1300 ft
- WADES COUNTRY STOREUnderground Storage Tanks · 1300 ft
- 086N25W05BCAB 15874 1963Stanhope 4Nitrate · 1400 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Stanhope'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 Stanhope.
Total Sites
67
within ~10 miles of Stanhope
Risk Level
Moderate
Highest-severity
4 Toxics Release Inventory facilities
Sources Checked
within ~10 miles of Stanhope
Severity Distribution
within ~10 miles of Stanhope
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Stanhope, Nitrate runs higher than the national average — 22 sites within ~10 miles of Stanhope. 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 Stanhope
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 Stanhope average
Your land is one point inside Stanhope
Everything above resolves to Stanhope as a whole — one PHZM band and one 28°F frost record, read across 627 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 Stanhope Average
Stanhope Average
- ●USDA Zones 5a, averaged across Stanhope
- ●One soil character for all of Stanhope
- ●Frost dates read at Stanhope's scale: Apr 15 to Oct 21
YOUR Parcel
- ✓Your exact zone, not Stanhope's 5a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Stanhope
Pull a site-specific report for your exact address in Stanhope, Iowa — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Stanhope averages can't show:
We read public map data around Stanhope — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Stanhope average
How we know this about Stanhope
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 Stanhope’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 Stanhope
When does frost risk typically end in Stanhope?
The last hard freeze (28°F) in Stanhope typically lands around Apr 15, 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 6.
When is the first frost in Stanhope?
The first hard freeze (28°F) in Stanhope 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 189 days after the spring freeze cleared.
How long is the growing season in Stanhope?
Measured between 28°F hard freezes, Stanhope sees about 189 frost-free days — roughly Apr 15 through Oct 21, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 6 to Oct 7, about 154 days.
Is the soil safe to grow vegetables in Stanhope?
The federal record around Stanhope shows 67 documented sites, mostly Underground Storage Tanks entries (34), 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 Stanhope?
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 Stanhope's scale — its 5a band and its 189-day season. Your yard writes its own version of Stanhope'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 Stanhope’s own scale
6 of the readings below were taken at Stanhope's own scale — its own ~189-day season between 28°F freezes, the 627 acres it covers and 67 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Stanhope's own USDA hardiness band, zones 5aUSDA PHZM 2023
- Stanhope's own 28°F hard-freeze dates, about Apr 15 and Oct 21 and the ~189-day span between themNOAA 1991–2020 Climate Normals
- 67 documented contamination sites on the federal record near Stanhope, the closest Underground Storage Tanks record under a tenth of a mile out from the town centreFederal environmental registers
- Stanhope's boundary and the 627 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5a and a ~189-day seasonGrowable Ground crop-matching engine
- The ecoregion at Stanhope'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 Stanhope's 627 acres read through its county's SSURGO summaryfrom Hamilton County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Hamilton 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 Hamilton County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Stanhope's 627 acreswhy one lot differs from the next →
- Which side of Stanhope you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 627 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 Stanhope-wide figureread your own land →
More in Iowa
Wider growing context
What grows across IowaStanhope sits outside our named growing regions, so Iowa as a whole is its closest context here.
Nearby growing guides