Flat Rock, Indiana, sits in USDA hardiness zone 6b — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
A short list that earns its place here — cabbage, hazelnut, lavender, and collard greens — with any one site's soil, sun, and drainage making the final cut.
Even in Flat Rock, 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 Flat Rock 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 Flat Rock — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Flat Rock — the short answer
Flat Rock, Indiana: USDA zone 6b, about 216 days between hard freezes, across 223 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 5
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~216
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 223 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 Flat Rock's average, not your lot's — a low corner or a tree line moves it. Against Flat Rock's 216-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Flat Rock
Each reading below is measured for Flat Rock itself — here is what it means for a garden here, and the move an experienced grower makes about it.

Season length
MeasuredFlat Rock 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
MeasuredFlat Rock 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 Flat Rock is in
Flat Rock sits in the Eastern Corn Belt Plains — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Flat Rock's own centroid rather than borrowed from Shelby County.
What Grows in Flat Rock
Every plant below cleared Flat Rock's own zone 6b and its 216-day season. Each card opens that plant's Indiana profile. How we score.






























Is it too late to plant in Flat Rock?
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 5 — 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 Flat Rock
Survey cells within 31 miles of Flat Rock checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 60 miles off. What to watch for.
What's on the federal record near Flat Rock
Closest first, within ~10 miles of Flat Rock. Listing isn't leaking, and distance isn't exposure.
- TENNELLS AUTO SERVICEUnderground Storage Tanks · 950 ft
- CAVE STONE INCORPORATEDUnderground Storage Tanks · 1400 ft
- DAVE OMARA CONTRACTOR INC - PLANT 9Toxics Release Inventory · 1.1 mi
- Sphalerite OccurrenceMining · 2.8 mi
- ANDREWS GROCERYUnderground Storage Tanks · 3.1 mi
- NIEBEL AUTOUnderground Storage Tanks · 3.9 mi
- AT & T T15 CARRIER STATIONUnderground Storage Tanks · 4.0 mi
- VIGORO INDUSTRIESUnderground Storage Tanks · 4.0 mi
- NADING MECHANICAL INCORPORATEDUnderground Storage Tanks · 4.9 mi
- MORRIS MICHAELUnderground Storage Tanks · 5.0 mi
- BP GAS STATIONUnderground Storage Tanks · 5.1 mi
- AUTO SERVICE CENTERUnderground Storage Tanks · 5.2 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Flat Rock'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 Flat Rock.
Total Sites
158
within ~10 miles of Flat Rock
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
within ~10 miles of Flat Rock
Severity Distribution
within ~10 miles of Flat Rock
Highest-Severity Sites

A note from Gnorman
What an experienced grower watches for around here
In and around Flat Rock, two things run higher than the national average within ~10 miles of Flat Rock — PFAS (3 sites) and Underground Storage Tanks (100 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.
Underground Storage Tanks: Underground storage tanks are the single most common source of soil contamination near homes and gardens.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Use raised beds with imported soil — this eliminates the primary soil-contact pathway.
Check your specific parcel in Flat Rock
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 Flat Rock average
Your land is one point inside Flat Rock
Everything above resolves to Flat Rock as a whole — one PHZM band and one 28°F frost record, read across 223 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 Flat Rock Average
Flat Rock Average
- ●USDA Zones 6b, averaged across Flat Rock
- ●One soil character for all of Flat Rock
- ●Frost dates read at Flat Rock's scale: Apr 3 to Nov 5
YOUR Parcel
- ✓Your exact zone, not Flat Rock's 6b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Flat Rock
Pull a site-specific report for your exact address in Flat Rock, Indiana — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Flat Rock averages can't show:
We read public map data around Flat Rock — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Flat Rock average
How we know this about Flat Rock
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 Flat Rock’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 Flat Rock
When does frost risk typically end in Flat Rock?
The last hard freeze (28°F) in Flat Rock 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 Flat Rock?
The first hard freeze (28°F) in Flat Rock typically arrives around Nov 5, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 22, so the watching starts about Oct 6 — about 216 days after the spring freeze cleared.
How long is the growing season in Flat Rock?
Measured between 28°F hard freezes, Flat Rock sees about 216 frost-free days — roughly Apr 3 through Nov 5, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 24 to Oct 22, about 181 days.
Is the soil safe to grow vegetables in Flat Rock?
The federal record around Flat Rock is a meaningful one — 158 documented sites, mostly Underground Storage Tanks entries (100), 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 Flat Rock?
From about Oct 6 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 5 (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 5. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Flat Rock's scale — its 6b band and its 216-day season. Your yard writes its own version of Flat Rock'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 Flat Rock’s own scale
7 of the readings below were taken at Flat Rock's own scale — its own ~216-day season between 28°F freezes, the 223 acres it covers and 158 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Flat Rock's own USDA hardiness band, zones 6bUSDA PHZM 2023
- Flat Rock's own 28°F hard-freeze dates, about Apr 3 and Nov 5 and the ~216-day span between themNOAA 1991–2020 Climate Normals
- 158 documented contamination sites on the federal record near Flat Rock, the closest Underground Storage Tanks record about 0.2 miles out from the town centreFederal environmental registers
- Flat Rock's boundary and the 223 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6b and a ~216-day seasonGrowable Ground crop-matching engine
- The ecoregion at Flat Rock's own centroid, the Eastern Corn Belt PlainsUS EPA Level III Ecoregions
- Lanternfly survey cells around Flat Rock 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 Flat Rock's 223 acres read through its county's SSURGO summaryfrom Shelby County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Shelby 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 Shelby County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Flat Rock's 223 acreswhy one lot differs from the next →
- Which side of Flat Rock you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 223 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 Flat Rock-wide figureread your own land →
More in Indiana
Wider growing context
What grows across IndianaFlat Rock sits outside our named growing regions, so Indiana as a whole is its closest context here.
Nearby growing guides
