Coal City, Indiana, 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.
Crops well matched to these conditions include cabbage, hazelnut, lavender, and collard greens — though what thrives on any one site still turns on its specific soil, sun, and drainage.
Even in Coal 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 Coal 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 Coal City — soil, climate, flood, and parcel records. How we handle your address.
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Coal City — the short answer
Coal City, Indiana: USDA zone 6b, about 213 days between hard freezes, across 232 acres of town.
- USDA zone
- 6b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 3
- 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
- ~213
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 232 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 Coal City's average, not your lot's — a low corner or a tree line moves it. Against Coal City's 213-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Coal City
Each reading below is measured for Coal City itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredCoal City runs about 213 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
MeasuredCoal 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 Coal City is in
Coal City sits in the Interior River Valleys and Hills — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Coal City's own centroid, and it is not what its county reads: Owen County is mostly Interior Plateau. The wider page above you is answering a different question about different ground.
What Grows in Coal City
Every plant below cleared Coal City's own zone 6b and its 213-day season. Each card opens that plant's Indiana profile. How we score.
Is it too late to plant in Coal City?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Mar 6; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 3 (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. 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 Coal City
Survey cells within 31 miles of Coal City checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 109 miles off. What to watch for.
What's on the federal record near Coal City
Closest first, within ~10 miles of Coal City. Listing isn't leaking, and distance isn't exposure.
- Coal City Service StationUnderground Storage Tanks · 1200 ft
- WC-51 COAL CITY, IND.Nitrate · 2400 ft
- Sinders Tire Removal IncorporatedUnderground Storage Tanks · 1.9 mi
- FRED H MITCHELLUnderground Storage Tanks · 2.9 mi
- WC-72 CLAY CITY, IND.Nitrate · 3.7 mi
- ACE IN THE HOLE MINEToxics Release Inventory · 4.1 mi
- WC-24 CLAY CITY, IND.Nitrate · 4.6 mi
- JOHNSTOWN STATIONBrownfields · 4.6 mi
- Citizens Gas & Coke Utility Johnstown Compressor StationUnderground Storage Tanks · 4.6 mi
- MARY PACKEYUnderground Storage Tanks · 4.8 mi
- NAWQA AG WELL FA9 NEAR BRUNSWICK, INNitrate · 4.9 mi
- CLAY CITY HIGH SCHOOLSUnderground Storage Tanks · 5.0 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Coal 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 Coal City.
Total Sites
83
within ~10 miles of Coal City
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
within ~10 miles of Coal City
Severity Distribution
within ~10 miles of Coal City
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Coal City, Nitrate runs higher than the national average — 32 sites within ~10 miles of Coal City. That's not a problem with your land — it's information about it.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in Coal 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 Coal City average
Your land is one point inside Coal City
Everything above resolves to Coal City as a whole — one PHZM band and one 28°F frost record, read across 232 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 Coal City Average
Coal City Average
- ●USDA Zones 6b, averaged across Coal City
- ●One soil character for all of Coal City
- ●Frost dates read at Coal City's scale: Apr 3 to Nov 2
YOUR Parcel
- ✓Your exact zone, not Coal City's 6b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Coal City
Pull a site-specific report for your exact address in Coal City, Indiana — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Coal City averages can't show:
We read public map data around Coal City — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Coal City average
How we know this about Coal 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 Coal 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 Coal City
When does frost risk typically end in Coal City?
The last hard freeze (28°F) in Coal City typically lands around Apr 3, 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 24.
When is the first frost in Coal City?
The first hard freeze (28°F) in Coal 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 213 days after the spring freeze cleared.
How long is the growing season in Coal City?
Measured between 28°F hard freezes, Coal City sees about 213 frost-free days — roughly Apr 3 through Nov 2, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 24 to Oct 19, about 178 days.
Is the soil safe to grow vegetables in Coal City?
The federal record around Coal City is a meaningful one — 83 documented sites, mostly Underground Storage Tanks entries (41), the nearest Underground Storage Tanks record about 0.2 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 Coal 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 Coal City's scale — its 6b band and its 213-day season. Your yard writes its own version of Coal 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 Coal City’s own scale
7 of the readings below were taken at Coal City's own scale — its own ~213-day season between 28°F freezes, the 232 acres it covers and 83 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Coal City's own USDA hardiness band, zones 6bUSDA PHZM 2023
- Coal City's own 28°F hard-freeze dates, about Apr 3 and Nov 2 and the ~213-day span between themNOAA 1991–2020 Climate Normals
- 83 documented contamination sites on the federal record near Coal City, the closest Underground Storage Tanks record about 0.2 miles out from the town centreFederal environmental registers
- Coal City's boundary and the 232 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6b and a ~213-day seasonGrowable Ground crop-matching engine
- Coal City sits in the Interior River Valleys and Hills — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
- Lanternfly survey cells around Coal City 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 Coal City's 232 acres read through its county's SSURGO summaryfrom Owen County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Owen County
- The growing challenges every Indiana grower plans around — written at state scale, so they stay on the state guidefrom Indiana
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Owen County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Coal City's 232 acreswhy one lot differs from the next →
- Which side of Coal 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 232 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.2 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 Coal City-wide figureread your own land →