Cedarville, Illinois, sits in USDA hardiness zone 5a — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
Growers here do well with cabbage, cranberry, lavender, and collard greens — with the usual caveat that any single yard's soil, sun, and drainage cast the deciding vote.
Even in Cedarville, 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 Cedarville 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 Cedarville — soil, climate, flood, and parcel records. How we handle your address.
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Cedarville — the short answer
Cedarville, Illinois: USDA zone 5a, about 189 days between hard freezes, across 295 acres of town.
- USDA zone
- 5a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 15
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 21
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~189
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 295 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 Cedarville's average, not your lot's — a low corner or a tree line moves it. Against Cedarville's 189-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Cedarville
Each reading below is measured for Cedarville itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredCedarville runs about 189 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
MeasuredCedarville 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 Cedarville is in
Cedarville sits in the Central Corn Belt Plains — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Cedarville's own centroid rather than borrowed from Stephenson County.
What Grows in Cedarville
Every plant below cleared Cedarville's own zone 5a and its 189-day season. Each card opens that plant's Illinois profile. How we score.
Is it too late to plant in Cedarville?
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 18; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 15 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 21 — 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 Cedarville
Closest first, within ~10 miles of Cedarville. Listing isn't leaking, and distance isn't exposure.
- Kelley Williamson MobilUnderground Storage Tanks · 1000 ft
- Reed SerUnderground Storage Tanks · 1000 ft
- Cedarville Village OfUnderground Storage Tanks · 1600 ft
- Freeport Vault CoUnderground Storage Tanks · 2.1 mi
- ROBERTSON AUTOMOTIVEBrownfields · 2.1 mi
- FARM & FLEET OF FREEPORTBrownfields · 2.2 mi
- KOESTER DAIRYCAFO · 2.7 mi
- Buckeye TownshipUnderground Storage Tanks · 3.1 mi
- Gilt Edge Farms IncUnderground Storage Tanks · 3.7 mi
- FREEPORTPFAS · 3.9 mi
- OBERT FARMS, LLCCAFO · 4.2 mi
- Natl By Products IncUnderground Storage Tanks · 4.4 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Cedarville'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 Cedarville.
Total Sites
236
within ~10 miles of Cedarville
Risk Level
Elevated
Highest-severity
5 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Cedarville
Severity Distribution
within ~10 miles of Cedarville
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Cedarville, two things run higher than the national average within ~10 miles of Cedarville — CAFO (5 sites) and Superfund (5 sites). That's not a problem with your land — it's information about it.
CAFO: CAFOs pose a different contamination profile than chemical sources.
Superfund: Superfund sites represent the most severe contamination in the federal system.
Wash all produce consumed raw thoroughly, especially leafy greens grown near CAFOs.
Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).
Check your specific parcel in Cedarville
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 Cedarville average
Your land is one point inside Cedarville
Everything above resolves to Cedarville as a whole — one PHZM band and one 28°F frost record, read across 295 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 Cedarville Average
Cedarville Average
- ●USDA Zones 5a, averaged across Cedarville
- ●One soil character for all of Cedarville
- ●Frost dates read at Cedarville's scale: Apr 15 to Oct 21
YOUR Parcel
- ✓Your exact zone, not Cedarville's 5a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Cedarville
Pull a site-specific report for your exact address in Cedarville, Illinois — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Cedarville averages can't show:
We read public map data around Cedarville — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Cedarville average
How we know this about Cedarville
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 Cedarville’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 Cedarville
When does frost risk typically end in Cedarville?
The last hard freeze (28°F) in Cedarville typically lands around Apr 15, 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 6.
When is the first frost in Cedarville?
The first hard freeze (28°F) in Cedarville typically arrives around Oct 21, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 7, so the watching starts about Sep 21 — about 189 days after the spring freeze cleared.
How long is the growing season in Cedarville?
Measured between 28°F hard freezes, Cedarville sees about 189 frost-free days — roughly Apr 15 through Oct 21, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 6 to Oct 7, about 154 days.
Is the soil safe to grow vegetables in Cedarville?
The federal record around Cedarville is a meaningful one — 236 documented sites, mostly Underground Storage Tanks entries (125), 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 Cedarville?
From about Sep 21 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 21 (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 21. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Cedarville's scale — its 5a band and its 189-day season. Your yard writes its own version of Cedarville'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 Cedarville’s own scale
6 of the readings below were taken at Cedarville's own scale — its own ~189-day season between 28°F freezes, the 295 acres it covers and 236 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Cedarville's own USDA hardiness band, zones 5aUSDA PHZM 2023
- Cedarville's own 28°F hard-freeze dates, about Apr 15 and Oct 21 and the ~189-day span between themNOAA 1991–2020 Climate Normals
- 236 documented contamination sites on the federal record near Cedarville, the closest Underground Storage Tanks record about 0.2 miles out from the town centreFederal environmental registers
- Cedarville's boundary and the 295 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5a and a ~189-day seasonGrowable Ground crop-matching engine
- The ecoregion at Cedarville'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 Cedarville's 295 acres read through its county's SSURGO summaryfrom Stephenson County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Stephenson 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 Stephenson County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Cedarville's 295 acreswhy one lot differs from the next →
- Which side of Cedarville you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 295 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 Cedarville-wide figureread your own land →
More in Illinois
Wider growing context
What grows across IllinoisCedarville sits outside our named growing regions, so Illinois as a whole is its closest context here.
Nearby growing guides