Leavenworth County, in Kansas, sits in USDA hardiness zone 6b — a zone band wide enough that plant choice, not possibility, is the interesting question.
Among the crops suited to this profile: cabbage, hazelnut, lavender, and collard greens. The site-level story — soil, sun, drainage — decides the rest.
Leavenworth County lies within Greater Kansas City Metro (Kansas Side) — a regional growing area with its own character.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Leavenworth County holds more than one microclimate.
Soils and elevations shift across Leavenworth 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 Leavenworth County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Leavenworth County — the short answer
Leavenworth County, Kansas: USDA zone 6b, about 215 days between hard freezes, across 297K acres.
- USDA zone
- 6b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 1
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Nov 2
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~215
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 297K 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 6b is Leavenworth County's average, not your lot's — a low corner or a tree line moves it. Against Leavenworth County's 215-day season, see what your own ground reads.
Heat in Leavenworth County
Across a year, Leavenworth County accumulates about 3,791 growing degree days above 50°F, about 42 fewer than the middle Kansas county — ahead of 48 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 Leavenworth County
Across Leavenworth County, the ground is predominantly Mollisols, where Pawnee, Grundy, and Shelby are the most extensive named soil series. The soil is generally moderately well drained with a silty clay loam surface. Topsoil pH runs about 6.1–6.5, slightly acidic. Rainfall drains through hydrologic group C soils.
Soil order
Mollisols
Drainage
Moderately well drained
Prime farmland
37%
Hydric soils
2%
Soil still varies lot by lot — soil types explained.
How the ground varies across Leavenworth County
The USDA soil survey maps 51% of Leavenworth County as moderately well drained — but another 48% drains differently: 27% well drained, 16% somewhat poorly drained.
Pawnee is the most extensive named soil at 10% of mapped acres, then Grundy (10%) and Shelby (10%).
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 Leavenworth County
Each reading below is measured for Leavenworth 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 Leavenworth County are moderately well drained, in hydrologic group C — roughly the middle of the drainage range.
This is close to the middle most vegetables prefer: it holds enough water to carry a crop between rains without staying waterlogged. The catch is that a wet spring or a low corner can still tip it soggy.
Plant on the site as-is for most crops, but keep the lowest, slowest-draining beds for moisture-tolerant plantings.
USDA NRCS SSURGO
Surface pH
MeasuredTopsoil across Leavenworth County runs about pH 6.1–6.5, 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
MeasuredLeavenworth County runs about 215 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
MeasuredLeavenworth County sits in USDA hardiness zone 6b.
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 Leavenworth County is in
Leavenworth County spans 2 EPA Level III ecoregions — Central Irregular Plains (89%) and Western Corn Belt Plains (11%). Which one your land falls in changes what grows wild there and how the ground behaves, and a county-wide answer cannot tell you which.
What Grows in Leavenworth County
We scored all 1,086 plants against Leavenworth County's own USDA zone 6b and its own 215-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 Leavenworth County?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Mar 4; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 1 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 2 — long-season crops need about 90 days of runway, quick greens only 30. A long window like this one runs successions deep into fall — and even its last weeks take quick greens and garlic.
Documented around Leavenworth County
- Japanese beetle17 documented records
- monarch butterfly1,192 documented records
Sighting records, so they follow observers as much as insects.
What gets applied to farmland in Leavenworth County
USGS estimates 67,951 lb of Glyphosate on Leavenworth County farmland in 2019, its largest by weight, ahead of Acephate (37,518 lb) and Atrazine (30,148 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 Leavenworth County — and how to grow with it.
We checked the federal record across Leavenworth County — 386 documented sites across 6 of the 9 source types we track.
The most significant on record: 3 Superfund sites (none NPL-listed). Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.
There's a meaningful federal record across Leavenworth County — worth a look before you plant food, not a reason to hold back from growing. Proximity to a documented site is information, not a diagnosis of any one yard. A soil test before new food beds is the sensible precaution here, and the map shows exactly which sites sit where, so you can see what's actually near you.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
What's on the federal record near Leavenworth County
Closest first, across Leavenworth County. Listing isn't leaking, and distance isn't exposure.
- 10S 21E 10ACA 01Nitrate · 1.0 mi
- 10S 21E 02ADD 01Nitrate · 1.5 mi
- LEAVENWORTH COUNTY SHOPUnderground Storage Tanks · 1.9 mi
- 10S 21E 22DBC 01Nitrate · 2.1 mi
- 10S 21E 35BB 01Nitrate · 3.3 mi
- 10S 22E 04CCD 01Nitrate · 3.7 mi
- 10S 22E 09CDC 01Nitrate · 3.8 mi
- SOUTHERN STAR CENTRAL - TONGANOXIE STATIONBrownfields · 3.8 mi
- 10S 22E 29CBC 01Nitrate · 3.8 mi
- 10S 22E 30DDC 01Nitrate · 3.8 mi
- 10S 22E 28BAB 01Nitrate · 4.4 mi
- 09S 21E 29CDB 01Nitrate · 4.5 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Leavenworth 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 Leavenworth County.
Total Sites
386
across Leavenworth County
Risk Level
Elevated
Highest-severity
3 Superfund sites (none NPL-listed)
Sources Checked
across Leavenworth County
Severity Distribution
across Leavenworth County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Leavenworth County, two things run higher than the national average across Leavenworth County — PFAS (6 sites) and Nitrate (150 sites). It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in Leavenworth 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 Leavenworth County average
Your land is one point inside Leavenworth County
Everything above resolves to Leavenworth County as a whole — one PHZM band and one county frost record, read across 297K 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 Leavenworth County Average
Leavenworth County Average
- ●USDA Zones 6b, averaged across Leavenworth County
- ●One soil character for all of Leavenworth County
- ●Frost dates read at Leavenworth County's scale: Apr 1 to Nov 2
YOUR Parcel
- ✓Your exact zone, not Leavenworth County's 6b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Leavenworth County
Pull a site-specific report for your exact address in Leavenworth County, Kansas — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Leavenworth County averages can't show:
We read public map data around Leavenworth County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Leavenworth County average
How we know this about Leavenworth 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 Leavenworth County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Leavenworth County
When does frost risk typically end in Leavenworth County?
The last hard freeze (28°F) in Leavenworth County typically lands around Apr 1, 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 22.
How long is the growing season in Leavenworth County?
Measured between 28°F hard freezes, Leavenworth County sees about 215 frost-free days — roughly Apr 1 through Nov 2, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 22 to Oct 19, about 180 days.
Is the soil safe to grow vegetables in Leavenworth County?
The federal record around Leavenworth County is a meaningful one — 386 documented sites, mostly Nitrate entries (150), the nearest Nitrate record about 1.0 miles 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.
Everything above is measured at Leavenworth County's scale — its 6b band and its 215-day season. Your yard writes its own version of Leavenworth 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 Leavenworth County’s own scale
9 of the readings below were taken at Leavenworth County's own scale — its own ~215-day span between 28°F freezes, the 3 most extensive soil series mapped here and 386 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Leavenworth County's own USDA hardiness band, zones 6bUSDA PHZM 2023
- Leavenworth County's own 28°F hard-freeze dates and its ~215-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Leavenworth CountyUSDA NRCS SSURGO
- 386 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Nitrate record about 1.0 miles outFederal environmental registers
- Leavenworth County's boundary and the 296,581 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6b and a ~215-day seasonGrowable Ground crop-matching engine
- The 2 ecoregions Leavenworth County spans, Central Irregular Plains the largestUS EPA Level III Ecoregions
- Open occurrence records documented in Leavenworth County for 2 tracked speciesGBIF derived datasets (CC0 / CC BY 4.0)
- Which agricultural compounds go onto Leavenworth 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 Leavenworth County — the ~215 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 Leavenworth County's 296,581 acreswhy one lot differs from the next →
- Which of those 386 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 Leavenworth Countyread your own land →