Callaway County, in Missouri, sits in USDA hardiness zone 6b — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
Reliable performers under these conditions include cabbage, hazelnut, lavender, and collard greens; what your own ground favors still comes down to its soil, sun, and drainage.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Callaway County holds more than one microclimate.
Soils and elevations shift across Callaway 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 Callaway County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Callaway County — the short answer
Callaway County, Missouri: USDA zone 6b, about 217 days between hard freezes, across 534K 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 4
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~217
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 534K 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 Callaway County's average, not your lot's — a low corner or a tree line moves it. Against Callaway County's 217-day season, see what your own ground reads.
Heat in Callaway County
Across a year, Callaway County accumulates about 3,685 growing degree days above 50°F, about 68 fewer than the middle Missouri county — ahead of 45 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 Callaway County
Across Callaway County, the ground is predominantly Alfisols, where Keswick, Mexico, and Goss are the most extensive named soil series. The soil is generally well drained with a silt loam surface. Topsoil pH runs about 5.7–6.5, slightly acidic. Rainfall drains through hydrologic group D soils.
Soil order
Alfisols
Drainage
Well drained
Prime farmland
3%
Hydric soils
19%
Soil still varies lot by lot — soil types explained.
How the ground varies across Callaway County
The USDA soil survey maps 35% of Callaway County as well drained — but another 65% drains differently: 32% somewhat poorly drained, 17% poorly drained.
Keswick is the most extensive named soil at 18% of mapped acres, then Mexico (14%) and Goss (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 Callaway County
Each reading below is measured for Callaway 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 Callaway County are well drained, in hydrologic group D — 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 Callaway County runs about pH 5.7–6.5, 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 19% of Callaway 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
MeasuredCallaway County runs about 217 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 Callaway County is in
Callaway County spans 2 EPA Level III ecoregions — Interior River Valleys and Hills (72%) and Central Irregular Plains (28%). 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 Callaway County
We scored all 1,086 plants against Callaway County's own USDA zone 6b and its own 217-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 Callaway County?
Too late for some crops, right on time for others — a growing season is a sequence, not a deadline. 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 4 — 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 Callaway County
Survey cells within 31 miles of Callaway County checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 283 miles off. What to watch for.
- Japanese beetle1 documented records
- monarch butterfly2 documented records
Sighting records, so they follow observers as much as insects.
What gets applied to farmland in Callaway County
USGS estimates 68,561 lb of Glyphosate on Callaway County farmland in 2019, its largest by weight, ahead of Metolachlor & Metolachlor-s (31,554 lb) and Atrazine (27,562 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 Callaway County — and how to grow with it.
We checked the federal record across Callaway County — 285 documented sites across 6 of the 9 source types we track.
The most significant on record: 9 Toxics Release Inventory facilities. Active industrial facilities reporting chemical releases to air, water, and land.
There's a meaningful federal record across Callaway 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 Callaway County
Closest first, across Callaway County. Listing isn't leaking, and distance isn't exposure.
- FULTON RECEPTION & DIAGNOSTIC CENTERBrownfields · 2000 ft
- FULTON RECEPTION & DIAGNOSTIC CENTERUnderground Storage Tanks · 0.7 mi
- FULTON STATE HOSPITAL-FULTONBrownfields · 1.1 mi
- CREMER THERAPEUTIC CTRBrownfields · 1.1 mi
- FULTON STATE HOSPITALUnderground Storage Tanks · 1.1 mi
- DANUSER MACHINE COMPANY LLCBrownfields · 1.1 mi
- T47N R09W 16ACB1Nitrate · 1.2 mi
- MISSOURI SCHOOL FOR THE DEAFBrownfields · 1.3 mi
- MISSOURI SCHOOL FOR THE DEAFUnderground Storage Tanks · 1.3 mi
- CLARK SUPER 100 - SOLD TO VIRGINIAUnderground Storage Tanks · 1.5 mi
- STRIDE RITE SHOE CORP - FULTONToxics Release Inventory · 1.5 mi
- DAVIS SCHOOL BUS COUnderground Storage Tanks · 1.5 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Callaway 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 Callaway County.
Total Sites
285
across Callaway County
Risk Level
Elevated
Highest-severity
9 Toxics Release Inventory facilities
Sources Checked
across Callaway County
Severity Distribution
across Callaway County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Callaway County, two things run higher than the national average across Callaway County — CAFO (9 sites) and Nitrate (110 sites). That's not a problem with your land — it's information about it.
CAFO: CAFOs pose a different contamination profile than chemical sources.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Wash all produce consumed raw thoroughly, especially leafy greens grown near CAFOs.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in Callaway 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 Callaway County average
Your land is one point inside Callaway County
Everything above resolves to Callaway County as a whole — one PHZM band and one county frost record, read across 534K 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 Callaway County Average
Callaway County Average
- ●USDA Zones 6b, averaged across Callaway County
- ●One soil character for all of Callaway County
- ●Frost dates read at Callaway County's scale: Apr 1 to Nov 4
YOUR Parcel
- ✓Your exact zone, not Callaway County's 6b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Callaway County
Pull a site-specific report for your exact address in Callaway County, Missouri — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Callaway County averages can't show:
We read public map data around Callaway County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Callaway County average
How we know this about Callaway 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 Callaway County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Callaway County
When does frost risk typically end in Callaway County?
The last hard freeze (28°F) in Callaway 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 Callaway County?
Measured between 28°F hard freezes, Callaway County sees about 217 frost-free days — roughly Apr 1 through Nov 4, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 22 to Oct 21, about 182 days.
Is the soil safe to grow vegetables in Callaway County?
The federal record around Callaway County is a meaningful one — 285 documented sites, mostly Nitrate entries (110), the nearest Brownfields record about 0.4 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 Callaway County's scale — its 6b band and its 217-day season. Your yard writes its own version of Callaway 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 Callaway County’s own scale
9 of the readings below were taken at Callaway County's own scale — its own ~217-day span between 28°F freezes, the 3 most extensive soil series mapped here and 285 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Callaway County's own USDA hardiness band, zones 6bUSDA PHZM 2023
- Callaway County's own 28°F hard-freeze dates and its ~217-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Callaway CountyUSDA NRCS SSURGO
- 285 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Brownfields record about 0.4 miles outFederal environmental registers
- Callaway County's boundary and the 534,121 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6b and a ~217-day seasonGrowable Ground crop-matching engine
- The 2 ecoregions Callaway County spans, Interior River Valleys and Hills the largestUS EPA Level III Ecoregions
- Open occurrence records documented in Callaway County for 2 tracked speciesGBIF derived datasets (CC0 / CC BY 4.0)
- Which agricultural compounds go onto Callaway 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 Callaway County — the ~217 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 Callaway County's 534,121 acreswhy one lot differs from the next →
- Which of those 285 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 Callaway Countyread your own land →