What Grows in Rockford, Illinois

USDA Zones 5b · 42K acres

Rockford, Illinois, sits in USDA hardiness zone 5b — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.

Well-matched crops include cabbage, cranberry, lavender, and collard greens, and the gap between "grows in the area" and "grows in your yard" is closed by soil, sun, and drainage.

Score your parcel · free

Even in Rockford, 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 Rockford 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 Rockford — soil, climate, flood, and parcel records. How we handle your address.

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Rockford — the short answer

Rockford, Illinois: USDA zone 5b, about 195 days between hard freezes, across 42K 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
42K 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

5b5b
3a (Cold)13b (Hot)

Zone 5b is Rockford's average, not your lot's — a low corner or a tree line moves it. Against Rockford's 195-day season, see what your own ground reads.

Soil varies lot by lot — soil types explained.

What this means for growing in Rockford

Each reading below is measured for Rockford itself — here is what it means for a garden here, and the move an experienced grower makes about it.

Season length

Measured

Rockford 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

Measured

Rockford 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 Rockford is in

Rockford sits in the Southeastern Wisconsin Till Plains — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Rockford's own centroid, and it is not what its county reads: Winnebago County is mostly Central Corn Belt Plains. The wider page above you is answering a different question about different ground.

What that means for soil

What Grows in Rockford

Every plant below cleared Rockford's own zone 5b and its 195-day season. Each card opens that plant's Illinois profile. How we score.

cabbage, photograph
Growing cabbage in IllinoisZones 2–11Rockford's 5b — 3 zones of cold margin.
cranberry, photograph
Illinois cranberry guideZones 2–7Rockford's 5b — 3 zones of cold margin.
lavender, photograph
Lavender in IllinoisZones 5–8Rockford's 5b is its exact cold limit.
collard greens, photograph
Collard greens: Illinois growing notesZones 2–11Rockford's 5b — 3 zones of cold margin.
hazelnut, photograph
Growing hazelnut in IllinoisZones 4–9Rockford's 5b — 1 zone of cold margin.
St. Johns wort, photograph
Illinois st. johns wort guideZones 3–8Rockford's 5b — 2 zones of cold margin.
garlic, photograph
Garlic in IllinoisZones 2–10Rockford's 5b — 3 zones of cold margin.
blueberry, photograph
Blueberry: Illinois growing notesZones 3–8Rockford's 5b — 2 zones of cold margin.
Turkish rocket, photograph
Growing turkish rocket in IllinoisRockford's 195 days clear the ~90 it needs.
kale, photograph
Illinois kale guideZones 2–11Rockford's 5b — 3 zones of cold margin.
apple, photograph
Apple in IllinoisZones 3–8Rockford's 5b — 2 zones of cold margin.
lentil, photograph
Lentil: Illinois growing notesZones 2–11Rockford's 195 days clear the ~70 it needs.
okra, photograph
Growing okra in IllinoisZones 2–12Rockford's 195 days clear the ~50 it needs.
potato, photograph
Illinois potato guideZones 2–11Rockford's 5b — 3 zones of cold margin.
pumpkin, photograph
Pumpkin in IllinoisZones 3–11Rockford's 195 days clear the ~40 it needs.
hosta, photograph
Hosta: Illinois growing notesZones 3–8Rockford's 5b — 2 zones of cold margin.
sunflower, photograph
Growing sunflower in IllinoisZones 2–11Rockford's 195 days clear the ~70 it needs.
azalea, photograph
Illinois azalea guideZones 4–8Rockford's 5b — 1 zone of cold margin.
hops, photograph
Hops in IllinoisZones 3–8Rockford's 5b — 2 zones of cold margin.
iris, photograph
Iris: Illinois growing notesZones 3–10Rockford's 5b — 2 zones of cold margin.
French marigold, photograph
Growing french marigold in IllinoisRockford's 195 days clear the ~50 it needs.
lilac, photograph
Illinois lilac guideZones 4–10Rockford's 5b — 1 zone of cold margin.
American bittersweet, photograph
American bittersweet in IllinoisZones 3–8Rockford's 5b — 2 zones of cold margin.
Canada anemone, photograph
Canada anemone: Illinois growing notesZones 3–8Rockford's 5b — 2 zones of cold margin.
American elm, photograph
Growing american elm in IllinoisZones 3–9Rockford's 5b — 2 zones of cold margin.
alfalfa, photograph
Illinois alfalfa guideZones 2–10Rockford's 195 days clear the ~100 it needs.
Kentucky bluegrass, botanical illustration
Kentucky bluegrass in IllinoisZones 2–7Rockford's 5b — 3 zones of cold margin.
blue spruce, photograph
Blue spruce: Illinois growing notesZones 2–8Rockford's 5b — 3 zones of cold margin.
annual ryegrass, photograph
Growing annual ryegrass in IllinoisZones 3–10Rockford's 195 days clear the ~90 it needs.
Canada wild rye, photograph
Illinois canada wild rye guideZones 3–8Rockford's 5b — 2 zones of cold margin.

Is it too late to plant in Rockford?

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. As the window narrows, the plantings just get faster — fall brassicas, then greens, then garlic to finish.

What's on the federal record near Rockford

Closest first, within ~10 miles of Rockford. Listing isn't leaking, and distance isn't exposure.

  1. BUTITTA BROS RADIATOR INCBrownfields · 650 ft
  2. Stop N Go #521Underground Storage Tanks · 900 ft
  3. ANDROCK HARDWAREBrownfields · 1100 ft
  4. Webb William EUnderground Storage Tanks · 1100 ft
  5. BALLARD DECORATINGBrownfields · 1200 ft
  6. NAVY CLUBBrownfields · 1200 ft
  7. WALGREENS #3322Brownfields · 1400 ft
  8. Thrift Remsen PrintersUnderground Storage Tanks · 1600 ft
  9. ADVANCE AUTO PARTS # 104261Brownfields · 1600 ft
  10. Watkins Motor LinesUnderground Storage Tanks · 1800 ft
  11. Il Bell Telephone CoUnderground Storage Tanks · 1800 ft
  12. AT&T SERVICES INC EHSBrownfields · 1800 ft

6 more sites are on the record inside the same radius. See them on the map

Measured from Rockford'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 Rockford.

Total Sites

1,601

within ~10 miles of Rockford

Risk Level

High

Highest-severity

22 Superfund sites

Severity Distribution

within ~10 miles of Rockford

High7Moderate355Low1,239

Highest-Severity Sites

Interstate Pollution Control, INC.
Superfund · Superfund NPL
North Park Pwd
PFAS Sampling · PFAS Detected
Pagel'S Pit
Superfund · Superfund NPL
Rockford, Il
PFAS Sampling · PFAS Detected

A note from Gnorman

What an experienced grower watches for around here

In and around Rockford, two things run higher than the national average within ~10 miles of Rockford — Toxics Release Inventory (138 sites) and Superfund (22 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.

Toxics Release Inventory: TRI facilities report annual chemical releases to air, water, and land.

Superfund: Superfund sites represent the most severe contamination in the federal system.

Check prevailing wind direction — downwind parcels face higher exposure than upwind or crosswind locations.

Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).

Free Report

Check your specific parcel in Rockford

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 Rockford average

Your land is one point inside Rockford

Everything above resolves to Rockford as a whole — one PHZM band and one 28°F frost record, read across 42K 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 Rockford Average

Rockford Average

  • USDA Zones 5b, averaged across Rockford
  • One soil character for all of Rockford
  • Frost dates read at Rockford's scale: Apr 12 to Oct 24

YOUR Parcel

  • Your exact zone, not Rockford's 5b
  • Your SSURGO soil type & pH
  • Your sun exposure, cast in 3D

See MY Growing Report

Free Report

Read your specific parcel in Rockford

Pull a site-specific report for your exact address in Rockford, Illinois — soil, sun, drainage, frost risk, and scored plant recommendations.

Three things about your lot that Rockford averages can't show:

Your soil pHYour frost-free days — Rockford averages 195Your sun & shade

We read public map data around Rockford — soil, climate, flood, and parcel records. How we handle your address.

25+ data sources read at your address, not the Rockford average

How we know this about Rockford

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 Rockford’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 Rockford

When does frost risk typically end in Rockford?

The last hard freeze (28°F) in Rockford 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 Rockford?

The first hard freeze (28°F) in Rockford 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 Rockford?

Measured between 28°F hard freezes, Rockford 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 Rockford?

The federal record around Rockford runs heavier than most — 1,601 documented sites, mostly Underground Storage Tanks entries (791), the nearest Brownfields record about 0.1 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.

How do I protect my plants from frost in Rockford?

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 Rockford's scale — its 5b band and its 195-day season. Your yard writes its own version of Rockford'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 Rockford’s own scale

6 of the readings below were taken at Rockford's own scale — its own ~195-day season between 28°F freezes, the 41,800 acres it covers and 1,601 documented sites around it; 4 are borrowed from a wider read, named and linked below.

Measured here

  • Rockford's own USDA hardiness band, zones 5bUSDA PHZM 2023
  • Rockford's own 28°F hard-freeze dates, about Apr 12 and Oct 24 and the ~195-day span between themNOAA 1991–2020 Climate Normals
  • 1,601 documented contamination sites on the federal record near Rockford, the closest Brownfields record about 0.1 miles out from the town centreFederal environmental registers
  • Rockford's boundary and the 41,800 acres inside itUS Census TIGER/Line 2025
  • Which of 1,086 plants clear zones 5b and a ~195-day seasonGrowable Ground crop-matching engine
  • Rockford sits in the Southeastern Wisconsin Till Plains — not the ecoregion its county mostly readsUS EPA Level III Ecoregions

Inherited from a wider read

  • Soil character — no town-scale survey exists, so Rockford's 41,800 acres read through its county's SSURGO summaryfrom Winnebago County
  • Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Winnebago 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 Winnebago County

What this page can’t tell you

  • The soil pH, drainage, sun hours, and frost pockets on any one lot among Rockford's 41,800 acreswhy one lot differs from the next
  • Which side of Rockford you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 41,800 acresreading your own microclimate
  • How close that record sits to YOUR lot — the closest Brownfields record about 0.1 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 Rockford-wide figureread your own land
The next step finer is your own address

More in Illinois

Wider growing context

What grows across Illinois

Rockford sits outside our named growing regions, so Illinois as a whole is its closest context here.