Randolph County, in Missouri, sits in USDA hardiness zone 6b — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
A short list that earns its place here — tomato, peach, grape, and dogwood — with any one site's soil, sun, and drainage making the final cut.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Randolph County holds more than one microclimate.
Soils and elevations shift across Randolph County, so your frost dates and drainage aren't the county average. Enter your address and we'll score 1,112 plants against your land's actual soil, sun, and frost.
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
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Quick Facts
USDA Zones
6b
Last Hard Freeze (28°F)
Mar 15
County normal — light frosts run a few weeks later
First Hard Freeze (28°F)
Nov 21
County normal — light frosts arrive a few weeks earlier
County Area
309K acres
Hardiness Zone Range
Zone maps are averages across Randolph County. Your yard's slope, trees, and frost pockets shift what actually grows — see your land's exact reading.
Soil in Randolph County
Across Randolph County, the ground is predominantly Alfisols, where Keswick, Mexico, and Gosport are the most extensive named soil series. The soil is generally somewhat poorly drained with a silt loam surface. Topsoil pH runs about 5.8–6.5, slightly acidic. Rainfall drains through hydrologic group D soils.
Soil order
Alfisols
Drainage
Somewhat poorly drained
Prime farmland
8%
Hydric soils
32%
Soil still varies lot by lot — soil types explained.
What Grows in Randolph County
Plants matched to Randolph County's USDA zones 6b — each links to its full growing profile.
Is it too late to plant in Randolph County?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Feb 15; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 15 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 21 — long-season crops need about 90 days of runway, quick greens only 30. Here the season winds down slowly: late sowings, a real autumn harvest, and garlic in the ground before the first hard freeze.
Growing Challenges in Missouri
What an experienced grower plans around here — each one has a move.
Highly variable weather with late frosts and early heat
Let your local frost normals call the plantings — Missouri springs punish the calendar-planters and reward the patient.
Heavy clay soils in many regions
Raised beds solve clay drainage the first weekend — and yearly compost turns the ground under them into loam.
Ozark soils are thin and rocky
One soil test shows what thin Ozark ground actually holds — then build up with compost or beds where the depth runs out.
For cultivar selection, pest pressure, and planting-time guidance specific to Missouri, the MU Extension is the authoritative local source.
Safe to Grow Here?
What the federal record shows across Randolph County — and how to grow with it.
We checked the federal record across Randolph County — 149 documented sites across 7 of the 9 source types we track.
The most significant on record: 2 Superfund sites. 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 Randolph 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.
Environmental Intelligence
Understanding what's nearby helps you make informed decisions about where and how to grow.
Sources Checked
across Randolph County
Severity Distribution
across Randolph County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Randolph County, two things run higher than the national average — PFAS (3 sites) and CAFO (3 sites). That's not a problem with your land — it's information about 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 Randolph County
Get exact proximity distances to contamination sources for your specific parcel — plus soil, sun, drainage, and 1,112 plant recommendations.
Three things about your exact spot that zone averages miss:
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources analyzed in seconds
Your Specific Parcel Matters
Randolph County Average
- ●USDA Zones 6b
- ●Generic soil type for the area
- ●State-average frost dates
YOUR Parcel
- ✓Your exact hardiness zone
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Randolph County
Pull a site-specific report for your exact address in Randolph County, Missouri — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your exact spot that zone averages miss:
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources analyzed in seconds
Key Growing Facts for Randolph County, Missouri
- USDA Hardiness Zones: 6b (USDA PHZM 2023)
- Last Hard Freeze (28°F): Mar 15 (county normal, NOAA 1991–2020 Climate Normals — light frosts can follow for a few weeks)
- First Hard Freeze (28°F): Nov 21 (county normal, NOAA 1991–2020 Climate Normals — light frosts can arrive a few weeks earlier)
- Days Between Hard Freezes: ~251 (county normal, NOAA 1991–2020 Climate Normals)
- County Land Area: 309K acres (US Census TIGER 2025)
Zone data: USDA ARS Plant Hardiness Zone Map 2023. Climate data: NOAA NCEI. County boundaries: US Census TIGER/Line 2025.
Frost dates here are the Randolph County average. Low spots and tree cover move them by days on any one yard — see your exact frost windows.
Frequently Asked Questions
What hardiness zone is Randolph County, Missouri?
Randolph County sits in USDA hardiness zone 6b, per the USDA Plant Hardiness Zone Map 2023. Zones reflect average annual extreme minimum temperatures from 1991–2020 weather data.
Is it too late to plant in Randolph County?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Feb 15; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 15 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 21 — long-season crops need about 90 days of runway, quick greens only 30. Here the season winds down slowly: late sowings, a real autumn harvest, and garlic in the ground before the first hard freeze.
When does frost risk typically end in Randolph County?
The last hard freeze (28°F) in Randolph County typically lands around Mar 15, per NOAA 1991–2020 climate normals — an earlier marker than the light-frost dates many planting charts quote. That marks the hard freeze, not the last light frost — light frosts can still bite for a few more weeks, so tender transplants usually wait another 2–3 weeks.
How long is the growing season in Randolph County?
Measured between 28°F hard freezes, Randolph County sees about 251 frost-free days — roughly Mar 15 through Nov 21, per NOAA 1991–2020 climate normals. Tender crops get a somewhat shorter practical window, since lighter frosts reach a few weeks past the hard-freeze dates on both ends.
What vegetables grow in Randolph County?
Randolph County's zone 6b supports a wide range — strong performers include Tomato, Peach, Grape, Dogwood, and Blackberry. What actually takes on any one site comes down to its soil, sun, and drainage, and we score each plant against the real conditions at your address.
Which hardiness zone is Randolph County, really?
Officially, Randolph County sits in USDA zone 6b (USDA PHZM 2023) — but a zone is a 30-year average of winter's coldest night across an area, and it can't see any one yard. A south-facing slope, a tree line, or a low frost pocket can shift a single site by half a zone either way, which is why neighboring gardeners often quote different numbers. We read the conditions at your exact address — soil, sun, slope, and frost — and score 1,112 plants against what's actually there.
Is the soil safe to grow vegetables in Randolph County?
The federal record around Randolph County is a meaningful one — 149 documented sites — 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.
Just moved to Randolph County — what should I know before planting?
Start with three facts. Randolph County sits in USDA zone 6b, which sets what survives winter; the last 28°F hard freeze typically clears around Mar 15, with about 251 frost-free days to work with (NOAA 1991–2020 climate normals); and 149 documented sites sit on the federal record here, so a soil test before food beds is the smart first step. From there, matching plants to your actual soil and sun is the fun part.
Everything on this page is a Randolph County average. Your yard writes its own version — 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.