Brookfield, Illinois, sits in USDA hardiness zone 6a — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
These conditions suit cabbage, blueberry, lavender, and collard greens — a starting list any specific site will trim or extend with its own soil, sun, and drainage.
Even in Brookfield, 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 Brookfield 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 Brookfield — soil, climate, flood, and parcel records. How we handle your address.
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Brookfield — the short answer
Brookfield, Illinois: USDA zone 6a, about 225 days between hard freezes, across 2K acres of town.
- USDA zone
- 6a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 1
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 12
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~225
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 2K 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 6a is Brookfield's average, not your lot's — a low corner or a tree line moves it. Against Brookfield's 225-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Brookfield
Each reading below is measured for Brookfield itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredBrookfield runs about 225 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
MeasuredBrookfield 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 Brookfield is in
Brookfield sits in the Central Corn Belt Plains — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Brookfield's own centroid rather than borrowed from Cook County.
What Grows in Brookfield
Every plant below cleared Brookfield's own zone 6a and its 225-day season. Each card opens that plant's Illinois profile. How we score.
Is it too late to plant in Brookfield?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Mar 4; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 1 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 12 — long-season crops need about 90 days of runway, quick greens only 30. There is slack in a calendar like this — late plantings, second rounds of favorites, and a fall bench that keeps beds working.
Documented around Brookfield
Spotted lanternfly documented 10 miles from Brookfield, first recorded 2023. What to watch for.
What's on the federal record near Brookfield
Closest first, within ~10 miles of Brookfield. Listing isn't leaking, and distance isn't exposure.
- BROOKFIELDPFAS · 25 ft
- Il Conf Of 7Th Day AdventistsUnderground Storage Tanks · 1100 ft
- MAGIC TOUCH CLEANERSBrownfields · 1300 ft
- First National Bank of BrookfieldUnderground Storage Tanks · 1300 ft
- CVS PHARMACY 8744Brownfields · 1500 ft
- Brookfield Village OfUnderground Storage Tanks · 1600 ft
- Maple CitgoUnderground Storage Tanks · 1700 ft
- COMPLETE AUTO SVCBrownfields · 1800 ft
- ARTHUR STREET MERCURYSuperfund · 2300 ft
- Brookfield N Riverside Wtr CommUnderground Storage Tanks · 0.5 mi
- Amoco Ss#24040 Fac#10632Underground Storage Tanks · 0.6 mi
- BROOKFIELD CAR CAREBrownfields · 0.6 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Brookfield'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 Brookfield.
Sources Checked
within ~10 miles of Brookfield
Severity Distribution
within ~10 miles of Brookfield
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Brookfield, two things run higher than the national average within ~10 miles of Brookfield — Toxics Release Inventory (629 sites) and PFAS (58 sites). That's not a problem with your land — it's information about it.
Toxics Release Inventory: TRI facilities report annual chemical releases to air, water, and land.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Check prevailing wind direction — downwind parcels face higher exposure than upwind or crosswind locations.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Check your specific parcel in Brookfield
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 Brookfield average
Your land is one point inside Brookfield
Everything above resolves to Brookfield as a whole — one PHZM band and one 28°F frost record, read across 2K 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 Brookfield Average
Brookfield Average
- ●USDA Zones 6a, averaged across Brookfield
- ●One soil character for all of Brookfield
- ●Frost dates read at Brookfield's scale: Apr 1 to Nov 12
YOUR Parcel
- ✓Your exact zone, not Brookfield's 6a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Brookfield
Pull a site-specific report for your exact address in Brookfield, Illinois — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Brookfield averages can't show:
We read public map data around Brookfield — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Brookfield average
How we know this about Brookfield
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 Brookfield’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 Brookfield
When does frost risk typically end in Brookfield?
The last hard freeze (28°F) in Brookfield typically lands around Apr 1, 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 22.
When is the first frost in Brookfield?
The first hard freeze (28°F) in Brookfield typically arrives around Nov 12, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 29, so the watching starts about Oct 13 — about 225 days after the spring freeze cleared.
How long is the growing season in Brookfield?
Measured between 28°F hard freezes, Brookfield sees about 225 frost-free days — roughly Apr 1 through Nov 12, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 22 to Oct 29, about 190 days.
Is the soil safe to grow vegetables in Brookfield?
The federal record around Brookfield is a meaningful one — 6,535 documented sites, mostly Underground Storage Tanks entries (3,264), the nearest PFAS record under a tenth of a mile 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 Brookfield?
From about Oct 13 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 12 (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 12. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Brookfield's scale — its 6a band and its 225-day season. Your yard writes its own version of Brookfield'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 Brookfield’s own scale
7 of the readings below were taken at Brookfield's own scale — its own ~225-day season between 28°F freezes, the 1,961 acres it covers and 6,535 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Brookfield's own USDA hardiness band, zones 6aUSDA PHZM 2023
- Brookfield's own 28°F hard-freeze dates, about Apr 1 and Nov 12 and the ~225-day span between themNOAA 1991–2020 Climate Normals
- 6,535 documented contamination sites on the federal record near Brookfield, the closest PFAS record under a tenth of a mile out from the town centreFederal environmental registers
- Brookfield's boundary and the 1,961 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6a and a ~225-day seasonGrowable Ground crop-matching engine
- The ecoregion at Brookfield's own centroid, the Central Corn Belt PlainsUS EPA Level III Ecoregions
- A documented spotted-lanternfly record within reach of Brookfieldlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so Brookfield's 1,961 acres read through its county's SSURGO summaryfrom Cook County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Cook 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 Cook County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Brookfield's 1,961 acreswhy one lot differs from the next →
- Which side of Brookfield you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 1,961 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest PFAS 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 Brookfield-wide figureread your own land →