Sycamore, Illinois, sits in USDA hardiness zone 5b — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
The conditions favor cabbage, cranberry, lavender, and collard greens, among others — though every individual site edits that list with its own soil, sun, and drainage.
Even in Sycamore, 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 Sycamore 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 Sycamore — soil, climate, flood, and parcel records. How we handle your address.
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Sycamore — the short answer
Sycamore, Illinois: USDA zone 5b, about 195 days between hard freezes, across 6K acres of city.
- USDA zone
- 5b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 12
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 24
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~195
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 6K 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 5b is Sycamore's average, not your lot's — a low corner or a tree line moves it. Against Sycamore's 195-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Sycamore
Each reading below is measured for Sycamore itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredSycamore runs about 195 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
MeasuredSycamore sits in USDA hardiness zone 5b.
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 Sycamore is in
Sycamore sits in the Central Corn Belt Plains — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Sycamore's own centroid rather than borrowed from DeKalb County.
What Grows in Sycamore
Every plant below cleared Sycamore's own zone 5b and its 195-day season. Each card opens that plant's Illinois profile. How we score.
Is it too late to plant in Sycamore?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Mar 15; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 12 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 24 — 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.
Documented around Sycamore
Spotted lanternfly documented 18 miles from Sycamore, first recorded 2023. What to watch for.
What's on the federal record near Sycamore
Closest first, within ~10 miles of Sycamore. Listing isn't leaking, and distance isn't exposure.
- SEYMOUR OF SYCAMOREBrownfields · 1500 ft
- DC LITHOGRAPHERSBrownfields · 1500 ft
- A NO 1 CAB INCBrownfields · 1700 ft
- CUSTOM COLLISION AUTOBODYBrownfields · 1700 ft
- Riverside MarathonUnderground Storage Tanks · 1700 ft
- Former Kerr Mcgee 7755Underground Storage Tanks · 1800 ft
- Consolidated Freightways TermUnderground Storage Tanks · 1800 ft
- Sycamore Maintenance YardUnderground Storage Tanks · 1800 ft
- Fasco Mills CompanyUnderground Storage Tanks · 2000 ft
- 41N 5E-32.1g1Nitrate · 2100 ft
- Share Oil CoUnderground Storage Tanks · 2300 ft
- Seymour Of Sycamore IncUnderground Storage Tanks · 2400 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Sycamore'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 Sycamore.
Total Sites
367
within ~10 miles of Sycamore
Risk Level
Elevated
Highest-severity
3 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Sycamore
Severity Distribution
within ~10 miles of Sycamore
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Sycamore, two things run higher than the national average within ~10 miles of Sycamore — PFAS (5 sites) and Toxics Release Inventory (30 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 Sycamore
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 Sycamore average
Your land is one point inside Sycamore
Everything above resolves to Sycamore as a whole — one PHZM band and one 28°F frost record, read across 6K 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 Sycamore Average
Sycamore Average
- ●USDA Zones 5b, averaged across Sycamore
- ●One soil character for all of Sycamore
- ●Frost dates read at Sycamore's scale: Apr 12 to Oct 24
YOUR Parcel
- ✓Your exact zone, not Sycamore's 5b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Sycamore
Pull a site-specific report for your exact address in Sycamore, Illinois — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Sycamore averages can't show:
We read public map data around Sycamore — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Sycamore average
How we know this about Sycamore
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 Sycamore’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 Sycamore
When does frost risk typically end in Sycamore?
The last hard freeze (28°F) in Sycamore typically lands around Apr 12, 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 3.
When is the first frost in Sycamore?
The first hard freeze (28°F) in Sycamore typically arrives around Oct 24, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 10, so the watching starts about Sep 24 — about 195 days after the spring freeze cleared.
How long is the growing season in Sycamore?
Measured between 28°F hard freezes, Sycamore sees about 195 frost-free days — roughly Apr 12 through Oct 24, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 3 to Oct 10, about 160 days.
Is the soil safe to grow vegetables in Sycamore?
The federal record around Sycamore is a meaningful one — 367 documented sites, mostly Underground Storage Tanks entries (188), the nearest Brownfields record about 0.3 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 Sycamore?
From about Sep 24 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 24 (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 24. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Sycamore's scale — its 5b band and its 195-day season. Your yard writes its own version of Sycamore'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 Sycamore’s own scale
7 of the readings below were taken at Sycamore's own scale — its own ~195-day season between 28°F freezes, the 6,478 acres it covers and 367 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Sycamore's own USDA hardiness band, zones 5bUSDA PHZM 2023
- Sycamore's own 28°F hard-freeze dates, about Apr 12 and Oct 24 and the ~195-day span between themNOAA 1991–2020 Climate Normals
- 367 documented contamination sites on the federal record near Sycamore, the closest Brownfields record about 0.3 miles out from the town centreFederal environmental registers
- Sycamore's boundary and the 6,478 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5b and a ~195-day seasonGrowable Ground crop-matching engine
- The ecoregion at Sycamore's own centroid, the Central Corn Belt PlainsUS EPA Level III Ecoregions
- A documented spotted-lanternfly record within reach of Sycamorelydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so Sycamore's 6,478 acres read through its county's SSURGO summaryfrom DeKalb County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom DeKalb 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 DeKalb County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Sycamore's 6,478 acreswhy one lot differs from the next →
- Which side of Sycamore you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 6,478 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields record about 0.3 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 Sycamore-wide figureread your own land →
More in Illinois
Wider growing context
What grows across IllinoisSycamore sits outside our named growing regions, so Illinois as a whole is its closest context here.
Nearby growing guides