Clarkton, Missouri, sits in USDA hardiness zone 7b — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
Reliable performers under these conditions include cabbage, prickly pear, california poppy, and collard greens; what your own ground favors still comes down to its soil, sun, and drainage.
Even in Clarkton, no two yards are alike.
A low spot, a south-facing slope, or a stand of trees moves the frost date and sun across a single Clarkton lot. 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 Clarkton — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Clarkton — the short answer
Clarkton, Missouri: USDA zone 7b, about 256 days between hard freezes, across 723 acres of city.
- USDA zone
- 7b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 11
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 22
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~256
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 723 acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are this town’s own 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 7b is Clarkton's average, not your lot's — a low corner or a tree line moves it. Against Clarkton's 256-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Clarkton
Each reading below is measured for Clarkton itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredClarkton runs about 256 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
MeasuredClarkton sits in USDA hardiness zone 7b.
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 Clarkton is in
Clarkton sits in the Mississippi Alluvial Plain — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Clarkton's own centroid rather than borrowed from Dunklin County.
What Grows in Clarkton
Every plant below cleared Clarkton's own zone 7b and its 256-day season. Each card opens that plant's Missouri profile. How we score.
Is it too late to plant in Clarkton?
For most of the year, no — what changes is which crops still fit the days remaining. Cool-season crops can go in from around Feb 11; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 11 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 22 — 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.
Documented around Clarkton
Survey cells within 31 miles of Clarkton checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 183 miles off. What to watch for.
What's on the federal record near Clarkton
Closest first, within ~10 miles of Clarkton. Listing isn't leaking, and distance isn't exposure.
- T21N R10E 22BAD1Nitrate · 200 ft
- FLASH MARKET #174Underground Storage Tanks · 800 ft
- T21N R10E 22BADNitrate · 800 ft
- T21N R10E 17CDC1Nitrate · 2.2 mi
- T21N R10E 09BBD1Nitrate · 2.4 mi
- SCHOOL DISTRICT OF GIDEON NO 37Underground Storage Tanks · 2.6 mi
- CASEYS GENERAL STORE #1883Underground Storage Tanks · 2.7 mi
- HATLEYS SERVICE STATIONUnderground Storage Tanks · 2.7 mi
- T21N R11E 19BBB1Nitrate · 3.0 mi
- GIDEON AIRPORTUnderground Storage Tanks · 3.3 mi
- CAMBELL AIRPORTUnderground Storage Tanks · 3.7 mi
- T & P EXPRESSUnderground Storage Tanks · 4.4 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Clarkton'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 Clarkton.
Sources Checked
within ~10 miles of Clarkton
Severity Distribution
within ~10 miles of Clarkton
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Clarkton, two things run higher than the national average within ~10 miles of Clarkton — PFAS (3 sites) and Nitrate (40 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.
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 Clarkton
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 Clarkton average
Your land is one point inside Clarkton
Everything above resolves to Clarkton as a whole — one PHZM band and one 28°F frost record, read across 723 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 city 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 local average.
Your Lot vs the Clarkton Average
Clarkton Average
- ●USDA Zones 7b, averaged across Clarkton
- ●One soil character for all of Clarkton
- ●Frost dates read at Clarkton's scale: Mar 11 to Nov 22
YOUR Parcel
- ✓Your exact zone, not Clarkton's 7b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Clarkton
Pull a site-specific report for your exact address in Clarkton, Missouri — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Clarkton averages can't show:
We read public map data around Clarkton — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Clarkton average
How we know this about Clarkton
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this city’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Clarkton’s own record; boundaries and acreage from US Census TIGER/Line 2025; the contamination records from the federal sources named in their beats above. Soil is not read at city grain anywhere on this page — there is no city-resolution survey in our data, which is why you will find no soil grid here rather than a statewide one wearing a local label. The resolution ledger below names every figure this page inherited.
Common questions about Clarkton
When does frost risk typically end in Clarkton?
The last hard freeze (28°F) in Clarkton typically lands around Mar 11, 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 1.
When is the first frost in Clarkton?
The first hard freeze (28°F) in Clarkton typically arrives around Nov 22, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 8, so the watching starts about Oct 23 — about 256 days after the spring freeze cleared.
How long is the growing season in Clarkton?
Measured between 28°F hard freezes, Clarkton sees about 256 frost-free days — roughly Mar 11 through Nov 22, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 1 to Nov 8, about 221 days.
Is the soil safe to grow vegetables in Clarkton?
The federal record around Clarkton is a meaningful one — 103 documented sites, mostly Underground Storage Tanks entries (56), the nearest Nitrate 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.
How do I protect my plants from frost in Clarkton?
From about Oct 23 the job here turns from planting to protecting — the last start even a 30-day crop can finish. As the season closes around the first 28°F hard freeze near Nov 22 (NOAA 1991–2020 climate normals), three moves buy time: row cover or an old sheet over tender plants on still, clear nights; water the soil the afternoon before a freeze, so it holds warmth overnight; and harvest tomatoes, peppers and basil before Nov 22. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Clarkton's scale — its 7b band and its 256-day season. Your yard writes its own version of Clarkton's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
What this page reads at Clarkton’s own scale
7 of the readings below were taken at Clarkton's own scale — its own ~256-day season between 28°F freezes, the 723 acres it covers and 103 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Clarkton's own USDA hardiness band, zones 7bUSDA PHZM 2023
- Clarkton's own 28°F hard-freeze dates, about Mar 11 and Nov 22 and the ~256-day span between themNOAA 1991–2020 Climate Normals
- 103 documented contamination sites on the federal record near Clarkton, the closest Nitrate record under a tenth of a mile out from the town centreFederal environmental registers
- Clarkton's boundary and the 723 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7b and a ~256-day seasonGrowable Ground crop-matching engine
- The ecoregion at Clarkton's own centroid, the Mississippi Alluvial PlainUS EPA Level III Ecoregions
- Lanternfly survey cells around Clarkton checked, none carrying a detectionlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so Clarkton's 723 acres read through its county's SSURGO summaryfrom Dunklin County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Dunklin County
- The growing challenges every Missouri grower plans around — written at state scale, so they stay on the state guidefrom Missouri
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Dunklin County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Clarkton's 723 acreswhy one lot differs from the next →
- Which side of Clarkton you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 723 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Nitrate record under a tenth of a mile out, measured from the town centrehow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — measured at your address, and averaged away by any Clarkton-wide figureread your own land →