Sloan, Iowa, sits in USDA hardiness zone 5a — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
These conditions suit cabbage, cranberry, lavender, and collard greens — a starting list any specific site will trim or extend with its own soil, sun, and drainage.
Even in Sloan, 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 Sloan 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 Sloan — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Sloan — the short answer
Sloan, Iowa: USDA zone 5a, about 186 days between hard freezes, across 370 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 18
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~186
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 370 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 Sloan's average, not your lot's — a low corner or a tree line moves it. Against Sloan's 186-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Sloan
Each reading below is measured for Sloan itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredSloan runs about 186 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
MeasuredSloan 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 Sloan is in
Sloan sits in the Western Corn Belt Plains — EPA Level III, inside the wider Great Plains. That is read at Sloan's own centroid rather than borrowed from Woodbury County.
What Grows in Sloan
Every plant below cleared Sloan's own zone 5a and its 186-day season. Each card opens that plant's Iowa profile. How we score.
Is it too late to plant in Sloan?
Usually not — gardeners here simply switch what goes in the ground as the season moves. 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 18 — long-season crops need about 90 days of runway, quick greens only 30. Late in the year the fall bench takes over — quick greens, radishes, and garlic that repays you next summer.
What's on the federal record near Sloan
Closest first, within ~10 miles of Sloan. Listing isn't leaking, and distance isn't exposure.
- IDOTUnderground Storage Tanks · 400 ft
- REMCO FARM CORPUnderground Storage Tanks · 400 ft
- SHOP & GOUnderground Storage Tanks · 400 ft
- WESTWOOD HIGH SCHOOLUnderground Storage Tanks · 750 ft
- NW IOWA TELEPHONEUnderground Storage Tanks · 850 ft
- 086N46W29CBDB SloanNitrate · 1100 ft
- 086N46W29CBDB 1947Sloan 2Nitrate · 1100 ft
- 086N46W29CBDB 1963Sloan 3Nitrate · 1200 ft
- CASEY''S GENERAL STORE 2597Underground Storage Tanks · 1600 ft
- PINGS SERVICEUnderground Storage Tanks · 1600 ft
- KIRKENDAHL STANDARDUnderground Storage Tanks · 1700 ft
- SLOAN PROPERTYUnderground Storage Tanks · 1700 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Sloan'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 Sloan.
Sources Checked
within ~10 miles of Sloan
Severity Distribution
within ~10 miles of Sloan
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Sloan, two things run higher than the national average within ~10 miles of Sloan — Toxics Release Inventory (8 sites) and Nitrate (26 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
Toxics Release Inventory: TRI facilities report annual chemical releases to air, water, and land.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Check prevailing wind direction — downwind parcels face higher exposure than upwind or crosswind locations.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in Sloan
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 Sloan average
Your land is one point inside Sloan
Everything above resolves to Sloan as a whole — one PHZM band and one 28°F frost record, read across 370 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 Sloan Average
Sloan Average
- ●USDA Zones 5a, averaged across Sloan
- ●One soil character for all of Sloan
- ●Frost dates read at Sloan's scale: Apr 15 to Oct 18
YOUR Parcel
- ✓Your exact zone, not Sloan's 5a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Sloan
Pull a site-specific report for your exact address in Sloan, Iowa — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Sloan averages can't show:
We read public map data around Sloan — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Sloan average
How we know this about Sloan
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 Sloan’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 Sloan
When does frost risk typically end in Sloan?
The last hard freeze (28°F) in Sloan 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 Sloan?
The first hard freeze (28°F) in Sloan typically arrives around Oct 18, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 4, so the watching starts about Sep 18 — about 186 days after the spring freeze cleared.
How long is the growing season in Sloan?
Measured between 28°F hard freezes, Sloan sees about 186 frost-free days — roughly Apr 15 through Oct 18, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 6 to Oct 4, about 151 days.
Is the soil safe to grow vegetables in Sloan?
The federal record around Sloan is a meaningful one — 81 documented sites, mostly Underground Storage Tanks entries (33), 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 Sloan?
From about Sep 18 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 18 (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 18. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Sloan's scale — its 5a band and its 186-day season. Your yard writes its own version of Sloan'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 Sloan’s own scale
6 of the readings below were taken at Sloan's own scale — its own ~186-day season between 28°F freezes, the 370 acres it covers and 81 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Sloan's own USDA hardiness band, zones 5aUSDA PHZM 2023
- Sloan's own 28°F hard-freeze dates, about Apr 15 and Oct 18 and the ~186-day span between themNOAA 1991–2020 Climate Normals
- 81 documented contamination sites on the federal record near Sloan, the closest Underground Storage Tanks record under a tenth of a mile out from the town centreFederal environmental registers
- Sloan's boundary and the 370 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5a and a ~186-day seasonGrowable Ground crop-matching engine
- The ecoregion at Sloan'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 Sloan's 370 acres read through its county's SSURGO summaryfrom Woodbury County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Woodbury 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 Woodbury County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Sloan's 370 acreswhy one lot differs from the next →
- Which side of Sloan you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 370 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 Sloan-wide figureread your own land →
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