Will County, in Illinois, sits in USDA hardiness zone 6a — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
Reliable performers under these conditions include cabbage, hazelnut, lavender, and collard greens; what your own ground favors still comes down to its soil, sun, and drainage.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Will County holds more than one microclimate.
Soils and elevations shift across Will County, so your frost dates and drainage aren't the county average. 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 Will County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Will County — the short answer
Will County, Illinois: USDA zone 6a, about 218 days between hard freezes, across 535K acres.
- USDA zone
- 6a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 4
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Nov 8
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~218
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 535K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are county 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 6a is Will County's average, not your lot's — a low corner or a tree line moves it. Against Will County's 218-day season, see what your own ground reads.
Heat in Will County
Across a year, Will County accumulates about 2,993 growing degree days above 50°F, about 390 fewer than the middle Illinois county — ahead of 18 of Illinois’s 102 counties. Degree days are the heat a crop actually gets to work with — more of them is more room to ripen a long-season crop before the freeze closes the window.
Grounded in PRISM Climate Group, Oregon State University — 1991–2020 monthly normals
Soil in Will County
Across Will County, the ground is predominantly Mollisols, where Elliott, Ashkum, and Ozaukee are the most extensive named soil series. The soil is generally somewhat poorly drained with a silt loam surface. Topsoil pH runs about 6.4–7.0, neutral. Rainfall drains through hydrologic group C/D soils.
Soil order
Mollisols
Drainage
Somewhat poorly drained
Prime farmland
54%
Hydric soils
31%
Soil still varies lot by lot — soil types explained.
How the ground varies across Will County
The USDA soil survey maps 35% of Will County as somewhat poorly drained — but another 62% drains differently: 29% poorly drained, 20% moderately well drained.
Elliott is the most extensive named soil at 16% of mapped acres, then Ashkum (16%) and Ozaukee (7%).
Which of them your own lot sits on is a parcel question, not a county one. Check your address for the survey at your boundary.
What this means for growing in Will County
Each reading below is measured for Will County itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Drainage
MeasuredThe dominant soils across Will County are somewhat poorly drained, in hydrologic group C/D — ground that sheds water slowly.
Beds can stay saturated for days after heavy rain, and the roots of most vegetables, berries, and fruit trees suffocate or rot in soil that never drains.
Raised beds or mounded rows lift roots above the wet zone; choose water-tolerant crops for the lowest spots.
USDA NRCS SSURGO
Surface pH
MeasuredTopsoil across Will County runs about pH 6.4–7.0, close to neutral.
This is the range most vegetables prefer — one correction you probably do not have to make, which is genuinely good news for a new bed.
Keep it there with compost rather than lime or sulfur, and only amend if your own soil test says otherwise.
USDA NRCS SSURGO
Season length
MeasuredWill County 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
MeasuredWill County sits in USDA hardiness zone 6a.
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 Will County is in
Will County sits in the Central Corn Belt Plains — EPA Level III, inside the wider Eastern Temperate Forests. One consistent ecological setting across the whole county.
What Grows in Will County
We scored all 1,086 plants against Will County's own USDA zone 6a and its own 218-day season between hard freezes, using the same matching engine that runs a full parcel report. These cleared both. Sun, soil pH and drainage vary lot by lot — those are the parcel questions below. Each card opens that plant's Illinois profile.
Is it too late to plant in Will County?
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 7; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 4 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 8 — 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 Will County
Spotted lanternfly documented 13 miles from Will County, first recorded 2023. What to watch for.
- Japanese beetle20 documented records
- monarch butterfly504 documented records
Sighting records, so they follow observers as much as insects.
What gets applied to farmland in Will County
USGS estimates 214,802 lb of Glyphosate on Will County farmland in 2019, its largest by weight, ahead of Acetochlor (99,842 lb) and Atrazine (93,506 lb).
Farmland across the whole county, not any one lot. Check your address for the site-by-site record.
Safe to Grow Here?
What the federal record shows across Will County — and how to grow with it.
We checked the federal record across Will County — 1,969 documented sites across 6 of the 9 source types we track.
The most significant on record: 26 Superfund sites. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.
Will County carries one of the heavier federal records we track — and that's not a verdict on your yard. Proximity to a documented site is information, not a diagnosis: nothing here says any particular parcel is affected. It does earn one concrete step — before food beds go in the ground, a professional soil test tells you exactly what you're working with, and raised beds with clean imported soil grow well almost anywhere in the meantime.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
What's on the federal record near Will County
Closest first, across Will County. Listing isn't leaking, and distance isn't exposure.
- Manhattan RepeaterUnderground Storage Tanks · 1.4 mi
- Manhattan Minit Mart #641Underground Storage Tanks · 1.5 mi
- Manhattan Twp Road DistUnderground Storage Tanks · 1.6 mi
- Aeropres CorporationUnderground Storage Tanks · 1.7 mi
- Manhattan Petrol, Inc.Underground Storage Tanks · 1.7 mi
- MANHATTAN COLLISION CTR INCBrownfields · 1.7 mi
- NICOR GAS STATION 249Brownfields · 1.8 mi
- Manhattan Fire Protection DistUnderground Storage Tanks · 1.8 mi
- Amoco PipelineUnderground Storage Tanks · 1.8 mi
- Heitman Trucking Co, Inc.Underground Storage Tanks · 2.0 mi
- CVS PHARMACY 4977Brownfields · 2.3 mi
- 7-Eleven Store #33334Underground Storage Tanks · 2.4 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Will County'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 Will County.
Sources Checked
across Will County
Severity Distribution
across Will County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Will County, two things run higher than the national average across Will County — PFAS (23 sites) and Toxics Release Inventory (157 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Toxics Release Inventory: TRI facilities report annual chemical releases to air, water, and land.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Check prevailing wind direction — downwind parcels face higher exposure than upwind or crosswind locations.
Check your specific parcel in Will County
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 Will County average
Your land is one point inside Will County
Everything above resolves to Will County as a whole — one PHZM band and one county frost record, read across 535K 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 county 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 county average.
Your Lot vs the Will County Average
Will County Average
- ●USDA Zones 6a, averaged across Will County
- ●One soil character for all of Will County
- ●Frost dates read at Will County's scale: Apr 4 to Nov 8
YOUR Parcel
- ✓Your exact zone, not Will County's 6a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Will County
Pull a site-specific report for your exact address in Will County, Illinois — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Will County averages can't show:
We read public map data around Will County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Will County average
How we know this about Will County
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at county grain; hard-freeze dates from NOAA 1991–2020 28°F normals at this county’s own record where one resolves, and the labelled statewide window where none does; soils from the USDA NRCS SSURGO survey, area-weighted across the county’s own map units; boundaries and acreage from US Census TIGER/Line 2025; the contamination and pesticide records from the federal sources named in their beats above. Where Will County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Will County
When does frost risk typically end in Will County?
The last hard freeze (28°F) in Will County typically lands around Apr 4, 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 25.
How long is the growing season in Will County?
Measured between 28°F hard freezes, Will County sees about 218 frost-free days — roughly Apr 4 through Nov 8, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 25 to Oct 25, about 183 days.
Is the soil safe to grow vegetables in Will County?
The federal record around Will County runs heavier than most — 1,969 documented sites, mostly Brownfields entries (910), the nearest Underground Storage Tanks record about 1.4 miles out — so test the soil before planting food in the ground, and raised beds with clean imported soil grow well in the meantime. Even here, proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what's recorded and where.
Everything above is measured at Will County's scale — its 6a band and its 218-day season. Your yard writes its own version of Will County's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
Will It Grow Here?
Zone fit is the first question — each answer below reads Illinois's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at Will County’s own scale
9 of the readings below were taken at Will County's own scale — its own ~218-day span between 28°F freezes, the 3 most extensive soil series mapped here and 1,969 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Will County's own USDA hardiness band, zones 6aUSDA PHZM 2023
- Will County's own 28°F hard-freeze dates and its ~218-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Will CountyUSDA NRCS SSURGO
- 1,969 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Underground Storage Tanks record about 1.4 miles outFederal environmental registers
- Will County's boundary and the 534,980 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6a and a ~218-day seasonGrowable Ground crop-matching engine
- Will County sitting wholly inside the Central Corn Belt PlainsUS EPA Level III Ecoregions
- Open occurrence records documented in Will County for 2 tracked speciesGBIF derived datasets (CC0 / CC BY 4.0)
- Which agricultural compounds go onto Will County farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every Illinois grower plans around — written at state scale, so they stay on the state guidefrom Illinois
What this page can’t tell you
- How the season shifts across Will County — the ~218 days above is one reading at its centre; the 12 towns below each carry their owntowns in this county →
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Will County's 534,980 acreswhy one lot differs from the next →
- Which of those 1,969 documented sites actually reaches your soil — that needs your address, the wind, and the groundwater directionhow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — none of it survives being averaged over Will Countyread your own land →