Wallace County, in Kansas, sits in USDA hardiness zone 6a — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
Among the crops suited to this profile: cabbage, hazelnut, lavender, and collard greens. The site-level story — soil, sun, drainage — decides the rest.
Wallace County lies within the High Plains — a regional growing area with its own character.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Wallace County holds more than one microclimate.
Soils and elevations shift across Wallace 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 Wallace County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Wallace County — the short answer
Wallace County, Kansas: USDA zone 6a, about 185 days between hard freezes, across 585K acres.
- USDA zone
- 6a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 19
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Oct 21
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~185
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 585K 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 6a is Wallace County's average, not your lot's — a low corner or a tree line moves it. Against Wallace County's 185-day season, see what your own ground reads.
Heat in Wallace County
Across a year, Wallace County accumulates about 3,187 growing degree days above 50°F, about 646 fewer than the middle Kansas county — ahead of 6 of Kansas’s 105 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 Wallace County
Across Wallace County, the ground is predominantly Mollisols, where Ulysses, Colby, and Keith are the most extensive named soil series. The soil is generally well drained with a silt loam surface. Topsoil pH runs about 7.4–7.9, slightly alkaline. Rainfall drains through hydrologic group B soils.
Soil order
Mollisols
Drainage
Well drained
Prime farmland
2%
Hydric soils
1%
Soil still varies lot by lot — soil types explained.
How the ground varies across Wallace County
The USDA soil survey maps 95% of Wallace County as well drained — but another 5% drains differently: 3% somewhat excessively drained, 1% somewhat poorly drained.
Ulysses is the most extensive named soil at 39% of mapped acres, then Colby (15%) and Keith (13%).
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 Wallace County
Each reading below is measured for Wallace 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 Wallace County are well drained, in hydrologic group B — ground that drains quickly.
The upside is soil you can work early in spring and roots that never drown; the cost is that fast-draining ground dries out fast and leaches nutrients away before plants can use them.
Work in compost and mulch to hold moisture and feed, and water more often in short doses than deep and rarely.
USDA NRCS SSURGO
Surface pH
MeasuredTopsoil across Wallace County runs about pH 7.4–7.9, on the alkaline side.
Many vegetables cope, but acid-lovers like blueberries struggle, and iron and manganese lock up above about pH 7.5 — leaves yellow between the veins even in rich soil.
Elemental sulfur and generous organic matter lower pH slowly for the beds that need it; test first so you add only what the soil actually calls for.
USDA NRCS SSURGO
Season length
MeasuredWallace County runs about 185 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
MeasuredWallace County sits in USDA hardiness zone 6a.
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 Wallace County is in
Wallace County sits in the High Plains — EPA Level III, inside the wider Great Plains. One consistent ecological setting across the whole county.
What Grows in Wallace County
We scored all 1,086 plants against Wallace County's own USDA zone 6a and its own 185-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 Kansas profile.
Is it too late to plant in Wallace 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 22; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 19 (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. Late in the year the fall bench takes over — quick greens, radishes, and garlic that repays you next summer.
Documented around Wallace County
- monarch butterfly41 documented records
Sighting records, so they follow observers as much as insects.
What gets applied to farmland in Wallace County
USGS estimates 204,298 lb of Atrazine on Wallace County farmland in 2019, its largest by weight, ahead of Glyphosate (178,079 lb) and Acetochlor (95,960 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 Wallace County — and how to grow with it.
We checked the federal record across Wallace County — 173 documented sites across 4 of the 9 source types we track.
The most significant on record: 1 concentrated animal feeding operation. Large-scale animal operations that can contaminate soil and groundwater with nitrates and pathogens.
The federal record across Wallace 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 Wallace County
Closest first, across Wallace County. Listing isn't leaking, and distance isn't exposure.
- 13S 40W 10ACC 01Nitrate · 1.5 mi
- 13S 40W 10ABB 01Nitrate · 1.7 mi
- BASF CORPORATION AT HELENA AGRI ENTERPRISESBrownfields · 1.8 mi
- 13S 40W 07AAC 01Nitrate · 1.9 mi
- THE 27/40 STORE, INCUnderground Storage Tanks · 2.0 mi
- SHAMROCK SERVICEUnderground Storage Tanks · 2.0 mi
- USD #241Underground Storage Tanks · 2.0 mi
- WALLACE COUNTYUnderground Storage Tanks · 2.2 mi
- KANSAS DEPT OF TRANSPORTATIONUnderground Storage Tanks · 2.2 mi
- COWLES MOTOR COUnderground Storage Tanks · 2.3 mi
- GAYLON WHITE TRUSTUnderground Storage Tanks · 2.3 mi
- DINKEL TIRE SERVICEUnderground Storage Tanks · 2.3 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Wallace 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 Wallace County.
Total Sites
173
across Wallace County
Risk Level
Moderate
Highest-severity
1 concentrated animal feeding operation
Sources Checked
across Wallace County
Severity Distribution
across Wallace County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Wallace County, Nitrate runs higher than the national average — 152 sites across Wallace 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 Wallace 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 Wallace County average
Your land is one point inside Wallace County
Everything above resolves to Wallace County as a whole — one PHZM band and one county frost record, read across 585K 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 Wallace County Average
Wallace County Average
- ●USDA Zones 6a, averaged across Wallace County
- ●One soil character for all of Wallace County
- ●Frost dates read at Wallace County's scale: Apr 19 to Oct 21
YOUR Parcel
- ✓Your exact zone, not Wallace County's 6a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Wallace County
Pull a site-specific report for your exact address in Wallace County, Kansas — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Wallace County averages can't show:
We read public map data around Wallace County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Wallace County average
How we know this about Wallace 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 Wallace County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Wallace County
When does frost risk typically end in Wallace County?
The last hard freeze (28°F) in Wallace County typically lands around Apr 19, 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 10.
How long is the growing season in Wallace County?
Measured between 28°F hard freezes, Wallace County sees about 185 frost-free days — roughly Apr 19 through Oct 21, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 10 to Oct 7, about 150 days.
Is the soil safe to grow vegetables in Wallace County?
The federal record around Wallace County shows 173 documented sites, mostly Nitrate entries (152), the nearest Nitrate record about 1.5 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 Wallace County's scale — its 6a band and its 185-day season. Your yard writes its own version of Wallace 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 Kansas's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at Wallace County’s own scale
9 of the readings below were taken at Wallace County's own scale — its own ~185-day span between 28°F freezes, the 3 most extensive soil series mapped here and 173 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Wallace County's own USDA hardiness band, zones 6aUSDA PHZM 2023
- Wallace County's own 28°F hard-freeze dates and its ~185-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Wallace CountyUSDA NRCS SSURGO
- 173 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Nitrate record about 1.5 miles outFederal environmental registers
- Wallace County's boundary and the 584,737 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6a and a ~185-day seasonGrowable Ground crop-matching engine
- Wallace County sitting wholly inside the High PlainsUS EPA Level III Ecoregions
- Open occurrence records documented in Wallace County for a tracked speciesGBIF derived datasets (CC0 / CC BY 4.0)
- Which agricultural compounds go onto Wallace County farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every Kansas grower plans around — written at state scale, so they stay on the state guidefrom Kansas
What this page can’t tell you
- How the season shifts across Wallace County — the ~185 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 Wallace County's 584,737 acreswhy one lot differs from the next →
- Which of those 173 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 Wallace Countyread your own land →