What Grows in Knox City, Missouri

USDA Zones 6a · 135 acres

Knox City, Missouri, sits in USDA hardiness zone 6a — a range where zone-matched perennials and frost-aware annual timing set what succeeds.

On paper, cabbage, hazelnut, lavender, and collard greens all suit these conditions — on the ground, soil, sun, and drainage make the final call.

Score your parcel · free

Even in Knox City, 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 Knox City 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 Knox City — soil, climate, flood, and parcel records. How we handle your address.

No card required · your full report in seconds

Knox City — the short answer

Knox City, Missouri: USDA zone 6a, about 216 days between hard freezes, across 135 acres of city.

USDA zone
6a
USDA PHZM 2023
Last hard freeze (28°F)
Mar 31
NOAA 1991–2020 Climate Normals, 28°F — this town
First hard freeze (28°F)
Nov 2
NOAA 1991–2020 Climate Normals, 28°F — this town
Days between freezes
~216
NOAA 1991–2020 Climate Normals, 28°F — this town
City area
135 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

6a6a
3a (Cold)13b (Hot)

Zone 6a is Knox City's average, not your lot's — a low corner or a tree line moves it. Against Knox City's 216-day season, see what your own ground reads.

Soil varies lot by lot — soil types explained.

What this means for growing in Knox City

Each reading below is measured for Knox City itself — here is what it means for a garden here, and the move an experienced grower makes about it.

Season length

Measured

Knox City runs about 216 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

Measured

Knox City sits in USDA hardiness zone 6a.

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 Knox City is in

Knox City sits in the Central Irregular Plains — EPA Level III, inside the wider Great Plains. That is read at Knox City's own centroid rather than borrowed from Knox County.

What that means for soil

What Grows in Knox City

Every plant below cleared Knox City's own zone 6a and its 216-day season. Each card opens that plant's Missouri profile. How we score.

cabbage, photograph
Growing cabbage in MissouriZones 2–11Knox City's 6a — 4 zones of cold margin.
hazelnut, photograph
Missouri hazelnut guideZones 4–9Knox City's 6a — 2 zones of cold margin.
lavender, photograph
Lavender in MissouriZones 5–8Knox City's 6a — 1 zone of cold margin.
collard greens, photograph
Collard greens: Missouri growing notesZones 2–11Knox City's 6a — 4 zones of cold margin.
blueberry, photograph
Growing blueberry in MissouriZones 3–8Knox City's 6a — 3 zones of cold margin.
California poppy, photograph
Missouri california poppy guideZones 6–10Knox City's 6a is its exact cold limit.
garlic, photograph
Garlic in MissouriZones 2–10Knox City's 6a — 4 zones of cold margin.
apple, photograph
Apple: Missouri growing notesZones 3–8Knox City's 6a — 3 zones of cold margin.
St. Johns wort, photograph
Growing st. johns wort in MissouriZones 3–8Knox City's 6a — 3 zones of cold margin.
kale, photograph
Missouri kale guideZones 2–11Knox City's 6a — 4 zones of cold margin.
pear, photograph
Pear in MissouriZones 4–8Knox City's 6a — 2 zones of cold margin.
Turkish rocket, photograph
Turkish rocket: Missouri growing notesKnox City's 216 days clear the ~90 it needs.
lentil, photograph
Growing lentil in MissouriZones 2–11Knox City's 216 days clear the ~70 it needs.
okra, photograph
Missouri okra guideZones 2–12Knox City's 216 days clear the ~50 it needs.
potato, photograph
Potato in MissouriZones 2–11Knox City's 6a — 4 zones of cold margin.
hosta, photograph
Hosta: Missouri growing notesZones 3–8Knox City's 6a — 3 zones of cold margin.
sunflower, photograph
Growing sunflower in MissouriZones 2–11Knox City's 216 days clear the ~70 it needs.
azalea, photograph
Missouri azalea guideZones 4–8Knox City's 6a — 2 zones of cold margin.
hops, photograph
Hops in MissouriZones 3–8Knox City's 6a — 3 zones of cold margin.
iris, photograph
Iris: Missouri growing notesZones 3–10Knox City's 6a — 3 zones of cold margin.
French marigold, photograph
Growing french marigold in MissouriKnox City's 216 days clear the ~50 it needs.
lilac, photograph
Missouri lilac guideZones 4–10Knox City's 6a — 2 zones of cold margin.
American bittersweet, photograph
American bittersweet in MissouriZones 3–8Knox City's 6a — 3 zones of cold margin.
tulip, photograph
Tulip: Missouri growing notesZones 6–8Knox City's 6a is its exact cold limit.
American elm, photograph
Growing american elm in MissouriZones 3–9Knox City's 6a — 3 zones of cold margin.
Ethiopian mustard, photograph
Missouri ethiopian mustard guideZones 4–10Knox City's 6a — 2 zones of cold margin.
Kentucky bluegrass, botanical illustration
Kentucky bluegrass in MissouriZones 2–7Knox City's 6a — 4 zones of cold margin.
Douglas fir, photograph
Douglas fir: Missouri growing notesZones 4–10Knox City's 6a — 2 zones of cold margin.
alfalfa, photograph
Growing alfalfa in MissouriZones 2–10Knox City's 216 days clear the ~100 it needs.
Canada wild rye, photograph
Missouri canada wild rye guideZones 3–8Knox City's 6a — 3 zones of cold margin.

Is it too late to plant in Knox City?

Almost never — the real question is what to plant next. Cool-season crops can go in from around Mar 3; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 31 (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.

What's on the federal record near Knox City

Closest first, within ~10 miles of Knox City. Listing isn't leaking, and distance isn't exposure.

  1. T62N R10W 21DCC1Nitrate · 0.8 mi
  2. NEW GENERATION PORK LLC NORTH BARNCAFO · 1.4 mi
  3. PINE VALLEY AUTO SALESBrownfields · 1.4 mi
  4. NEW GENERATION PORK LLC - SOUTHCAFO · 2.9 mi
  5. MILLER FARMS PORK PRODUCTIONCAFO · 3.2 mi
  6. LA BELLE MAINT LOTUnderground Storage Tanks · 4.9 mi
  7. JEY-LIN INCUnderground Storage Tanks · 5.2 mi
  8. ELVINS 66Underground Storage Tanks · 5.4 mi
  9. CASEYS GENERAL STORE #2601Underground Storage Tanks · 5.5 mi
  10. EDWARDS MFA SERVICEUnderground Storage Tanks · 6.0 mi
  11. SHELTON ZEISETCAFO · 6.0 mi
  12. MFA OIL CO LABELLE BULK PLANTBrownfields · 6.3 mi

6 more sites are on the record inside the same radius. See them on the map

Measured from Knox City'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 Knox City.

Total Sites

32

within ~10 miles of Knox City

Risk Level

Low

Highest-severity

6 concentrated animal feeding operations

Severity Distribution

within ~10 miles of Knox City

High0Moderate14Low18

Highest-Severity Sites

Cahalan Sinclair
Underground Storage Tanks · Open UST(S)
Caseys General Store #2600
Underground Storage Tanks · Open UST(S)
Northeast Mo Coop Station
Underground Storage Tanks · Open UST(S)
T61n R10w 25dcb1
Nitrate Monitoring · Well
T61n R10w 25dcb1
Nitrate Monitoring · Well

A note from Gnorman

What an experienced grower watches for around here

In and around Knox City, CAFO runs higher than the national average — 6 sites within ~10 miles of Knox City. Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.

CAFO: CAFOs pose a different contamination profile than chemical sources.

Wash all produce consumed raw thoroughly, especially leafy greens grown near CAFOs.

Free Report

Check your specific parcel in Knox City

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 Knox City average

Your land is one point inside Knox City

Everything above resolves to Knox City as a whole — one PHZM band and one 28°F frost record, read across 135 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 Knox City Average

Knox City Average

  • USDA Zones 6a, averaged across Knox City
  • One soil character for all of Knox City
  • Frost dates read at Knox City's scale: Mar 31 to Nov 2

YOUR Parcel

  • Your exact zone, not Knox City's 6a
  • Your SSURGO soil type & pH
  • Your sun exposure, cast in 3D

See MY Growing Report

Free Report

Read your specific parcel in Knox City

Pull a site-specific report for your exact address in Knox City, Missouri — soil, sun, drainage, frost risk, and scored plant recommendations.

Three things about your lot that Knox City averages can't show:

Your soil pHYour frost-free days — Knox City averages 216Your sun & shade

We read public map data around Knox City — soil, climate, flood, and parcel records. How we handle your address.

25+ data sources read at your address, not the Knox City average

How we know this about Knox City

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 Knox City’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 Knox City

When does frost risk typically end in Knox City?

The last hard freeze (28°F) in Knox City typically lands around Mar 31, 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 21.

When is the first frost in Knox City?

The first hard freeze (28°F) in Knox City typically arrives around Nov 2, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 19, so the watching starts about Oct 3 — about 216 days after the spring freeze cleared.

How long is the growing season in Knox City?

Measured between 28°F hard freezes, Knox City sees about 216 frost-free days — roughly Mar 31 through Nov 2, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 21 to Oct 19, about 181 days.

Is the soil safe to grow vegetables in Knox City?

The federal record around Knox City is light — 32 documented sites across the 9 federal source types we checked, mostly Underground Storage Tanks entries (16), the nearest Nitrate record about 0.8 miles out — and proximity to a documented site is information, not a diagnosis of any one yard. Growing food here starts from a strong position; a soil test before new food beds settles any site-specific question.

How do I protect my plants from frost in Knox City?

From about Oct 3 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 2 (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 2. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.

Everything above is measured at Knox City's scale — its 6a band and its 216-day season. Your yard writes its own version of Knox City'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 Knox City’s own scale

6 of the readings below were taken at Knox City's own scale — its own ~216-day season between 28°F freezes, the 135 acres it covers and 32 documented sites around it; 4 are borrowed from a wider read, named and linked below.

Measured here

  • Knox City's own USDA hardiness band, zones 6aUSDA PHZM 2023
  • Knox City's own 28°F hard-freeze dates, about Mar 31 and Nov 2 and the ~216-day span between themNOAA 1991–2020 Climate Normals
  • 32 documented contamination sites on the federal record near Knox City, the closest Nitrate record about 0.8 miles out from the town centreFederal environmental registers
  • Knox City's boundary and the 135 acres inside itUS Census TIGER/Line 2025
  • Which of 1,086 plants clear zones 6a and a ~216-day seasonGrowable Ground crop-matching engine
  • The ecoregion at Knox City's own centroid, the Central Irregular PlainsUS EPA Level III Ecoregions

Inherited from a wider read

  • Soil character — no town-scale survey exists, so Knox City's 135 acres read through its county's SSURGO summaryfrom Knox County
  • Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Knox 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 Knox County

What this page can’t tell you

  • The soil pH, drainage, sun hours, and frost pockets on any one lot among Knox City's 135 acreswhy one lot differs from the next
  • Which side of Knox City you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 135 acresreading your own microclimate
  • How close that record sits to YOUR lot — the closest Nitrate record about 0.8 miles 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 Knox City-wide figureread your own land
The next step finer is your own address

More in Missouri

Wider growing context

What grows across Missouri

Knox City sits outside our named growing regions, so Missouri as a whole is its closest context here.