Cass County, in Missouri, sits in USDA hardiness zone 6b — a zone band wide enough that plant choice, not possibility, is the interesting question.
Expect cabbage, hazelnut, lavender, and collard greens to be strong candidates here; the deciding factors on any one parcel stay local — soil, sun, and drainage.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Cass County holds more than one microclimate.
Soils and elevations shift across Cass 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 Cass County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Cass County — the short answer
Cass County, Missouri: USDA zone 6b, about 225 days between hard freezes, across 446K acres.
- USDA zone
- 6b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 28
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Nov 8
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~225
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 446K 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 Cass County's average, not your lot's — a low corner or a tree line moves it. Against Cass County's 225-day season, see what your own ground reads.
Heat in Cass County
Across a year, Cass County accumulates about 3,782 growing degree days above 50°F, about 29 more than the middle Missouri county — ahead of 61 of Missouri’s 115 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 Cass County
Across Cass County, the ground is predominantly Mollisols, where Kenoma, Snead, and Greenton are the most extensive named soil series. The soil is generally moderately well drained with a silt loam surface. Topsoil pH runs about 6.1–6.5, slightly acidic. Rainfall drains through hydrologic group D soils.
Soil order
Mollisols
Drainage
Moderately well drained
Prime farmland
21%
Hydric soils
16%
Soil still varies lot by lot — soil types explained.
How the ground varies across Cass County
The USDA soil survey maps 45% of Cass County as moderately well drained — but another 55% drains differently: 20% poorly drained, 17% well drained.
Kenoma is the most extensive named soil at 18% of mapped acres, then Snead (7%) and Greenton (7%).
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 Cass County
Each reading below is measured for Cass 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 Cass County are moderately well drained, in hydrologic group D — 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 Cass 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

Wet ground
MeasuredAbout 16% of Cass County is mapped as hydric — wetland — soil.
If your lot falls in one of those pockets, a standard in-ground bed will fight waterlogging all season, and roots that need air will struggle.
Check how your own ground drains before you dig; raised beds or moisture-loving plantings turn a wet corner from a problem into a niche.
USDA NRCS SSURGO

Season length
MeasuredCass County runs about 225 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
The kind of country Cass County is in
Cass 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 Cass County
We scored all 1,086 plants against Cass County's own USDA zone 6b and its own 225-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 Missouri profile.






























Is it too late to plant in Cass County?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Feb 28; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 28 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 8 — long-season crops need about 90 days of runway, quick greens only 30. With a season this long, “too late” mostly means “switch crops” — second sowings and a full fall garden are the norm, with garlic closing the year.
Documented around Cass County
- monarch butterfly373 documented records
Sighting records, so they follow observers as much as insects.
What gets applied to farmland in Cass County
USGS estimates 119,923 lb of Glyphosate on Cass County farmland in 2019, its largest by weight, ahead of Metolachlor & Metolachlor-s (56,623 lb) and Atrazine (53,266 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 Cass County — and how to grow with it.
We checked the federal record across Cass County — 308 documented sites across 7 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 Cass 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 Cass County
Closest first, across Cass County. Listing isn't leaking, and distance isn't exposure.
- HARRISONVILLE AUTO PARTSBrownfields · 350 ft
- TEXACO STATIONUnderground Storage Tanks · 350 ft
- V & L CONOCOUnderground Storage Tanks · 500 ft
- RAMSEY'S FEED & FARM SUPPLYUnderground Storage Tanks · 550 ft
- HARVEY'S - S.C. INCUnderground Storage Tanks · 650 ft
- HARRISONVILLE FIRE / EMERGENCY STATIONUnderground Storage Tanks · 1200 ft
- EVERYDAY STORE #4050Underground Storage Tanks · 1600 ft
- HARRISONVILLE MAINT FACILITYUnderground Storage Tanks · 1700 ft
- HARRISONVILLE MAINT LOTUnderground Storage Tanks · 1700 ft
- QUICK BREAK #4Underground Storage Tanks · 2300 ft
- MINIT MART #605 HARRISONVILLEUnderground Storage Tanks · 2300 ft
- WALGREENS #12778Brownfields · 2500 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Cass 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 Cass County.
Total Sites
308
across Cass County
Risk Level
Elevated
Highest-severity
3 Superfund sites (none NPL-listed)
Severity Distribution
across Cass County
Highest-Severity Sites

A note from Gnorman
What an experienced grower watches for around here
In and around Cass County, two things run higher than the national average across Cass County — PFAS (7 sites) and CAFO (3 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.
CAFO: CAFOs pose a different contamination profile than chemical sources.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Wash all produce consumed raw thoroughly, especially leafy greens grown near CAFOs.
Check your specific parcel in Cass 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 Cass County average
Your land is one point inside Cass County
Everything above resolves to Cass County as a whole — one PHZM band and one county frost record, read across 446K 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 Cass County Average
Cass County Average
- ●USDA Zones 6b, averaged across Cass County
- ●One soil character for all of Cass County
- ●Frost dates read at Cass County's scale: Mar 28 to Nov 8
YOUR Parcel
- ✓Your exact zone, not Cass County's 6b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Cass County
Pull a site-specific report for your exact address in Cass County, Missouri — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Cass County averages can't show:
We read public map data around Cass County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Cass County average
How we know this about Cass 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 Cass County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Cass County
When does frost risk typically end in Cass County?
The last hard freeze (28°F) in Cass County typically lands around Mar 28, 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 18.
How long is the growing season in Cass County?
Measured between 28°F hard freezes, Cass County sees about 225 frost-free days — roughly Mar 28 through Nov 8, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 18 to Oct 25, about 190 days.
Is the soil safe to grow vegetables in Cass County?
The federal record around Cass County is a meaningful one — 308 documented sites, mostly Underground Storage Tanks entries (150), the nearest Brownfields 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.
Everything above is measured at Cass County's scale — its 6b band and its 225-day season. Your yard writes its own version of Cass 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 Missouri's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at Cass County’s own scale
9 of the readings below were taken at Cass County's own scale — its own ~225-day span between 28°F freezes, the 3 most extensive soil series mapped here and 308 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Cass County's own USDA hardiness band, zones 6bUSDA PHZM 2023
- Cass County's own 28°F hard-freeze dates and its ~225-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Cass CountyUSDA NRCS SSURGO
- 308 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Brownfields record under a tenth of a mile outFederal environmental registers
- Cass County's boundary and the 445,835 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6b and a ~225-day seasonGrowable Ground crop-matching engine
- Cass County sitting wholly inside the Central Irregular PlainsUS EPA Level III Ecoregions
- Open occurrence records documented in Cass County for a tracked speciesGBIF derived datasets (CC0 / CC BY 4.0)
- Which agricultural compounds go onto Cass County farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every Missouri grower plans around — written at state scale, so they stay on the state guidefrom Missouri
What this page can’t tell you
- How the season shifts across Cass County — the ~225 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 Cass County's 445,835 acreswhy one lot differs from the next →
- Which of those 308 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 Cass Countyread your own land →
