Clay City, Illinois, sits in USDA hardiness zone 6b — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
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.
Even in Clay 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 Clay 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 Clay City — soil, climate, flood, and parcel records. How we handle your address.
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Clay City — the short answer
Clay City, Illinois: USDA zone 6b, about 218 days between hard freezes, across 1K acres of town.
- USDA zone
- 6b
- 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 4
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~218
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 1K 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 6b is Clay City's average, not your lot's — a low corner or a tree line moves it. Against Clay City's 218-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Clay City
Each reading below is measured for Clay City itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredClay City runs about 218 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
MeasuredClay City sits in USDA hardiness zone 6b.
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 Clay City is in
Clay City sits in the Interior River Valleys and Hills — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Clay City's own centroid rather than borrowed from Clay County.
What Grows in Clay City
Every plant below cleared Clay City's own zone 6b and its 218-day season. Each card opens that plant's Illinois profile. How we score.
Is it too late to plant in Clay City?
For most of the year, no — what changes is which crops still fit the days remaining. 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 4 — 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.
What's on the federal record near Clay City
Closest first, within ~10 miles of Clay City. Listing isn't leaking, and distance isn't exposure.
- J.W. DuffUnderground Storage Tanks · 550 ft
- Clay City High SchoolUnderground Storage Tanks · 1300 ft
- Lubert Schnautz Lumber CoUnderground Storage Tanks · 1500 ft
- H Cash Oil Field SerUnderground Storage Tanks · 1700 ft
- Barker TomUnderground Storage Tanks · 1800 ft
- J. W. RudyUnderground Storage Tanks · 2000 ft
- Casey's General Store #2557Underground Storage Tanks · 2500 ft
- Clay City Sewer PlantUnderground Storage Tanks · 2500 ft
- Shaffer Oil Field ServiceUnderground Storage Tanks · 2600 ft
- Natl Oil WellUnderground Storage Tanks · 0.8 mi
- Abner TruckingUnderground Storage Tanks · 1.1 mi
- Clay City OfficeUnderground Storage Tanks · 3.0 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Clay 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 Clay City.
Total Sites
91
within ~10 miles of Clay City
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
within ~10 miles of Clay City
Severity Distribution
within ~10 miles of Clay City
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Clay City, two things run higher than the national average within ~10 miles of Clay City — Toxics Release Inventory (8 sites) and Underground Storage Tanks (57 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
Toxics Release Inventory: TRI facilities report annual chemical releases to air, water, and land.
Underground Storage Tanks: Underground storage tanks are the single most common source of soil contamination near homes and gardens.
Check prevailing wind direction — downwind parcels face higher exposure than upwind or crosswind locations.
Use raised beds with imported soil — this eliminates the primary soil-contact pathway.
Check your specific parcel in Clay 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 Clay City average
Your land is one point inside Clay City
Everything above resolves to Clay City as a whole — one PHZM band and one 28°F frost record, read across 1K 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 town 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 Clay City Average
Clay City Average
- ●USDA Zones 6b, averaged across Clay City
- ●One soil character for all of Clay City
- ●Frost dates read at Clay City's scale: Mar 31 to Nov 4
YOUR Parcel
- ✓Your exact zone, not Clay City's 6b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Clay City
Pull a site-specific report for your exact address in Clay City, Illinois — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Clay City averages can't show:
We read public map data around Clay City — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Clay City average
How we know this about Clay City
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this town’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Clay 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 town grain anywhere on this page — there is no town-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 Clay City
When does frost risk typically end in Clay City?
The last hard freeze (28°F) in Clay 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 Clay City?
The first hard freeze (28°F) in Clay City typically arrives around Nov 4, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 21, so the watching starts about Oct 5 — about 218 days after the spring freeze cleared.
How long is the growing season in Clay City?
Measured between 28°F hard freezes, Clay City sees about 218 frost-free days — roughly Mar 31 through Nov 4, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 21 to Oct 21, about 183 days.
Is the soil safe to grow vegetables in Clay City?
The federal record around Clay City is a meaningful one — 91 documented sites, mostly Underground Storage Tanks entries (57), the nearest Underground Storage Tanks record about 0.1 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.
How do I protect my plants from frost in Clay City?
From about Oct 5 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 4 (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 4. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Clay City's scale — its 6b band and its 218-day season. Your yard writes its own version of Clay 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 Clay City’s own scale
6 of the readings below were taken at Clay City's own scale — its own ~218-day season between 28°F freezes, the 1,140 acres it covers and 91 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Clay City's own USDA hardiness band, zones 6bUSDA PHZM 2023
- Clay City's own 28°F hard-freeze dates, about Mar 31 and Nov 4 and the ~218-day span between themNOAA 1991–2020 Climate Normals
- 91 documented contamination sites on the federal record near Clay City, the closest Underground Storage Tanks record about 0.1 miles out from the town centreFederal environmental registers
- Clay City's boundary and the 1,140 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6b and a ~218-day seasonGrowable Ground crop-matching engine
- The ecoregion at Clay City's own centroid, the Interior River Valleys and HillsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Clay City's 1,140 acres read through its county's SSURGO summaryfrom Clay County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Clay County
- The growing challenges every Illinois grower plans around — written at state scale, so they stay on the state guidefrom Illinois
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Clay County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Clay City's 1,140 acreswhy one lot differs from the next →
- Which side of Clay 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 1,140 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.1 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 Clay City-wide figureread your own land →
More in Illinois
Wider growing context
What grows across IllinoisClay City sits outside our named growing regions, so Illinois as a whole is its closest context here.
Nearby growing guides