Wayne County, in Iowa, sits in USDA hardiness zone 5b — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
Well-matched crops include cabbage, cranberry, lavender, and collard greens, and the gap between "grows in the area" and "grows in your yard" is closed by soil, sun, and drainage.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Wayne County holds more than one microclimate.
Soils and elevations shift across Wayne County, so your frost dates and drainage aren't the county average. 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 Wayne County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Wayne County — the short answer
Wayne County, Iowa: USDA zone 5b, about 198 days between hard freezes, across 336K acres.
- USDA zone
- 5b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 10
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Oct 25
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~198
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 336K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are county 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 Wayne County's average, not your lot's — a low corner or a tree line moves it. Against Wayne County's 198-day season, see what your own ground reads.
Heat in Wayne County
Across a year, Wayne County accumulates about 2,903 growing degree days above 50°F, about 159 more than the middle Iowa county — ahead of 61 of Iowa’s 99 counties. Degree days are the heat a crop actually gets to work with — more of them is more room to ripen a long-season crop before the freeze closes the window.
Grounded in PRISM Climate Group, Oregon State University — 1991–2020 monthly normals
Soil in Wayne County
Across Wayne County, the ground is predominantly Mollisols, where Seymour, Gara, and Edina are the most extensive named soil series. The soil is generally somewhat poorly drained with a silty clay loam surface. Topsoil pH runs about 6.2–6.5, slightly acidic. Rainfall drains through hydrologic group D soils.
Soil order
Mollisols
Drainage
Somewhat poorly drained
Prime farmland
3%
Hydric soils
32%
Soil still varies lot by lot — soil types explained.
How the ground varies across Wayne County
The USDA soil survey maps 41% of Wayne County as somewhat poorly drained — but another 59% drains differently: 34% poorly drained, 22% well drained.
Seymour is the most extensive named soil at 17% of mapped acres, then Gara (8%) and Edina (8%).
Which of them your own lot sits on is a parcel question, not a county one. Check your address for the survey at your boundary.
What this means for growing in Wayne County
Each reading below is measured for Wayne County itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Drainage
MeasuredThe dominant soils across Wayne County are somewhat poorly drained, in hydrologic group D — ground that sheds water slowly.
Beds can stay saturated for days after heavy rain, and the roots of most vegetables, berries, and fruit trees suffocate or rot in soil that never drains.
Raised beds or mounded rows lift roots above the wet zone; choose water-tolerant crops for the lowest spots.
USDA NRCS SSURGO
Surface pH
MeasuredTopsoil across Wayne County runs about pH 6.2–6.5, close to neutral.
This is the range most vegetables prefer — one correction you probably do not have to make, which is genuinely good news for a new bed.
Keep it there with compost rather than lime or sulfur, and only amend if your own soil test says otherwise.
USDA NRCS SSURGO
Season length
MeasuredWayne County runs about 198 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
MeasuredWayne County 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 Wayne County is in
Wayne County sits in the Central Irregular Plains — EPA Level III, inside the wider Great Plains. One consistent ecological setting across the whole county.
What Grows in Wayne County
We scored all 1,086 plants against Wayne County's own USDA zone 5b and its own 198-day season between hard freezes, using the same matching engine that runs a full parcel report. These cleared both. Sun, soil pH and drainage vary lot by lot — those are the parcel questions below. Each card opens that plant's Iowa profile.
Is it too late to plant in Wayne County?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Mar 13; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 10 (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. 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 gets applied to farmland in Wayne County
USGS estimates 91,534 lb of Glyphosate on Wayne County farmland in 2019, its largest by weight, ahead of Metolachlor & Metolachlor-s (49,059 lb) and Atrazine (42,590 lb).
Farmland across the whole county, not any one lot. Check your address for the site-by-site record.
Safe to Grow Here?
What the federal record shows across Wayne County — and how to grow with it.
We checked the federal record across Wayne County — 97 documented sites across 4 of the 9 source types we track.
The most significant on record: 3 Toxics Release Inventory facilities. Active industrial facilities reporting chemical releases to air, water, and land.
The federal record across Wayne County is a modest one — a typical footprint for a growing area. Nothing here calls for alarm; it's worth knowing which recorded sites sit closest to where you grow, and each one on the map carries its type and location. If one turns out to be a near neighbor, a one-time soil test settles the question.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
What's on the federal record near Wayne County
Closest first, across Wayne County. Listing isn't leaking, and distance isn't exposure.
- EAST PENN MANUFACTURING CO., INCToxics Release Inventory · 1.1 mi
- EAST PENN MANUFACTURING CO., INCBrownfields · 1.1 mi
- CORYDON OIL COUnderground Storage Tanks · 1.4 mi
- CORYDON CONOCOUnderground Storage Tanks · 1.4 mi
- WAYNE COMMUNITY SCHOOLBrownfields · 1.4 mi
- WAYNE COMMUNITY HIGH SCHOOLUnderground Storage Tanks · 1.4 mi
- CORYDON USPSBrownfields · 1.4 mi
- D AND K STANDARDUnderground Storage Tanks · 1.5 mi
- VETTER EQUIPMENT COMPANYBrownfields · 1.5 mi
- ROD''S AUTO INCUnderground Storage Tanks · 1.5 mi
- DEFLECTA-SHIELD CORPToxics Release Inventory · 1.5 mi
- CASEY''S GENERAL STORE 2315Underground Storage Tanks · 1.5 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Wayne County'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 Wayne County.
Total Sites
97
across Wayne County
Risk Level
Moderate
Highest-severity
3 Toxics Release Inventory facilities
Sources Checked
across Wayne County
Severity Distribution
across Wayne County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Wayne County, Nitrate runs higher than the national average — 50 sites across Wayne County. 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 Wayne County
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 Wayne County average
Your land is one point inside Wayne County
Everything above resolves to Wayne County as a whole — one PHZM band and one county frost record, read across 336K 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 county 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 county average.
Your Lot vs the Wayne County Average
Wayne County Average
- ●USDA Zones 5b, averaged across Wayne County
- ●One soil character for all of Wayne County
- ●Frost dates read at Wayne County's scale: Apr 10 to Oct 25
YOUR Parcel
- ✓Your exact zone, not Wayne County's 5b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Wayne County
Pull a site-specific report for your exact address in Wayne County, Iowa — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Wayne County averages can't show:
We read public map data around Wayne County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Wayne County average
How we know this about Wayne County
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at county grain; hard-freeze dates from NOAA 1991–2020 28°F normals at this county’s own record where one resolves, and the labelled statewide window where none does; soils from the USDA NRCS SSURGO survey, area-weighted across the county’s own map units; boundaries and acreage from US Census TIGER/Line 2025; the contamination and pesticide records from the federal sources named in their beats above. Where Wayne County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Wayne County
When does frost risk typically end in Wayne County?
The last hard freeze (28°F) in Wayne County typically lands around Apr 10, 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 1.
How long is the growing season in Wayne County?
Measured between 28°F hard freezes, Wayne County sees about 198 frost-free days — roughly Apr 10 through Oct 25, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 1 to Oct 11, about 163 days.
Is the soil safe to grow vegetables in Wayne County?
The federal record around Wayne County shows 97 documented sites, mostly Nitrate entries (50), the nearest Toxics Release Inventory record about 1.1 miles 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.
Everything above is measured at Wayne County's scale — its 5b band and its 198-day season. Your yard writes its own version of Wayne County's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
Will It Grow Here?
Zone fit is the first question — each answer below reads Iowa's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at Wayne County’s own scale
8 of the readings below were taken at Wayne County's own scale — its own ~198-day span between 28°F freezes, the 3 most extensive soil series mapped here and 97 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Wayne County's own USDA hardiness band, zones 5bUSDA PHZM 2023
- Wayne County's own 28°F hard-freeze dates and its ~198-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Wayne CountyUSDA NRCS SSURGO
- 97 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Toxics Release Inventory record about 1.1 miles outFederal environmental registers
- Wayne County's boundary and the 336,300 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5b and a ~198-day seasonGrowable Ground crop-matching engine
- Wayne County sitting wholly inside the Central Irregular PlainsUS EPA Level III Ecoregions
- Which agricultural compounds go onto Wayne County farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every Iowa grower plans around — written at state scale, so they stay on the state guidefrom Iowa
What this page can’t tell you
- How the season shifts across Wayne County — the ~198 days above is one reading at its centre; the 12 towns below each carry their owntowns in this county →
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Wayne County's 336,300 acreswhy one lot differs from the next →
- Which of those 97 documented sites actually reaches your soil — that needs your address, the wind, and the groundwater directionhow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — none of it survives being averaged over Wayne Countyread your own land →