Lanark, Illinois, sits in USDA hardiness zone 5a — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
These conditions suit cabbage, cranberry, lavender, and collard greens — a starting list any specific site will trim or extend with its own soil, sun, and drainage.
Even in Lanark, 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 Lanark 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 Lanark — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Lanark — the short answer
Lanark, Illinois: USDA zone 5a, about 181 days between hard freezes, across 717 acres of city.
- USDA zone
- 5a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 19
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 17
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~181
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 717 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 5a is Lanark's average, not your lot's — a low corner or a tree line moves it. Against Lanark's 181-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Lanark
Each reading below is measured for Lanark itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredLanark runs about 181 days between hard freezes — a moderate growing season.
There is room for the full run of cool-season crops plus a warm-season main crop, but the calendar is tight enough that a late spring or early fall frost still decides how much finishes.
Time warm-season transplants to your last hard freeze, and a few weeks of season extension turns a near-miss harvest into a sure one.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredLanark sits in USDA hardiness zone 5a.
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 Lanark is in
Lanark sits in the Central Corn Belt Plains — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Lanark's own centroid rather than borrowed from Carroll County.
What Grows in Lanark
Every plant below cleared Lanark's own zone 5a and its 181-day season. Each card opens that plant's Illinois profile. How we score.
Is it too late to plant in Lanark?
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 22; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 19 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 17 — long-season crops need about 90 days of runway, quick greens only 30. Late in the year the fall bench takes over — quick greens, radishes, and garlic that repays you next summer.
What's on the federal record near Lanark
Closest first, within ~10 miles of Lanark. Listing isn't leaking, and distance isn't exposure.
- Lanark Ready Mix IncUnderground Storage Tanks · 150 ft
- CARROLL SVC COBrownfields · 600 ft
- Soo Line RailroadUnderground Storage Tanks · 700 ft
- 24N 6E- 5.5e1Nitrate · 750 ft
- Kelley Williamson MobilUnderground Storage Tanks · 950 ft
- Carroll Ser CoUnderground Storage Tanks · 950 ft
- Express Lane Gas-N-Food Mart, Inc.Underground Storage Tanks · 1000 ft
- IDOTBrownfields · 1500 ft
- ELKAY MANUFACTURING COToxics Release Inventory · 1700 ft
- ELKAY MANUFACTURING COBrownfields · 1700 ft
- Casey's General Store #3455Underground Storage Tanks · 2200 ft
- Buss DonUnderground Storage Tanks · 2300 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Lanark'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 Lanark.
Total Sites
86
within ~10 miles of Lanark
Risk Level
Moderate
Highest-severity
2 Toxics Release Inventory facilities
Sources Checked
within ~10 miles of Lanark
Severity Distribution
within ~10 miles of Lanark
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Lanark, CAFO runs higher than the national average — 12 sites within ~10 miles of Lanark. It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.
CAFO: CAFOs pose a different contamination profile than chemical sources.
Wash all produce consumed raw thoroughly, especially leafy greens grown near CAFOs.
Check your specific parcel in Lanark
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 Lanark average
Your land is one point inside Lanark
Everything above resolves to Lanark as a whole — one PHZM band and one 28°F frost record, read across 717 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 Lanark Average
Lanark Average
- ●USDA Zones 5a, averaged across Lanark
- ●One soil character for all of Lanark
- ●Frost dates read at Lanark's scale: Apr 19 to Oct 17
YOUR Parcel
- ✓Your exact zone, not Lanark's 5a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Lanark
Pull a site-specific report for your exact address in Lanark, Illinois — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Lanark averages can't show:
We read public map data around Lanark — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Lanark average
How we know this about Lanark
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 Lanark’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 Lanark
When does frost risk typically end in Lanark?
The last hard freeze (28°F) in Lanark typically lands around Apr 19, 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 May 10.
When is the first frost in Lanark?
The first hard freeze (28°F) in Lanark typically arrives around Oct 17, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 3, so the watching starts about Sep 17 — about 181 days after the spring freeze cleared.
How long is the growing season in Lanark?
Measured between 28°F hard freezes, Lanark sees about 181 frost-free days — roughly Apr 19 through Oct 17, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 10 to Oct 3, about 146 days.
Is the soil safe to grow vegetables in Lanark?
The federal record around Lanark shows 86 documented sites, mostly Underground Storage Tanks entries (49), the nearest Underground Storage Tanks record under a tenth of a mile out — a typical footprint for a growing area, and proximity to a documented site is information, not a diagnosis of any one yard. It's worth seeing which recorded sites sit closest to where you grow, and testing the soil before new food beds near any of them.
How do I protect my plants from frost in Lanark?
From about Sep 17 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 Oct 17 (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 Oct 17. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Lanark's scale — its 5a band and its 181-day season. Your yard writes its own version of Lanark'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 Lanark’s own scale
6 of the readings below were taken at Lanark's own scale — its own ~181-day season between 28°F freezes, the 717 acres it covers and 86 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Lanark's own USDA hardiness band, zones 5aUSDA PHZM 2023
- Lanark's own 28°F hard-freeze dates, about Apr 19 and Oct 17 and the ~181-day span between themNOAA 1991–2020 Climate Normals
- 86 documented contamination sites on the federal record near Lanark, the closest Underground Storage Tanks record under a tenth of a mile out from the town centreFederal environmental registers
- Lanark's boundary and the 717 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5a and a ~181-day seasonGrowable Ground crop-matching engine
- The ecoregion at Lanark's own centroid, the Central Corn Belt PlainsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Lanark's 717 acres read through its county's SSURGO summaryfrom Carroll County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Carroll 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 Carroll County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Lanark's 717 acreswhy one lot differs from the next →
- Which side of Lanark you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 717 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks 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 Lanark-wide figureread your own land →
More in Illinois
Wider growing context
What grows across IllinoisLanark sits outside our named growing regions, so Illinois as a whole is its closest context here.
Nearby growing guides