Marine City, Michigan, 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.
Among the crops suited to this profile: cabbage, hazelnut, lavender, and collard greens. The site-level story — soil, sun, drainage — decides the rest.
Even in Marine City, 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 Marine City 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 Marine City — soil, climate, flood, and parcel records. How we handle your address.
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Marine City — the short answer
Marine City, Michigan: USDA zone 6a, about 207 days between hard freezes, across 1K acres of city.
- USDA zone
- 6a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 14
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 7
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~207
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 1K 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 Marine City's average, not your lot's — a low corner or a tree line moves it. Against Marine City's 207-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Marine City
Each reading below is measured for Marine City itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredMarine City runs about 207 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
MeasuredMarine City 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 Marine City is in
Marine City sits in the Huron/Erie Lake Plains — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Marine City's own centroid rather than borrowed from St. Clair County.
What Grows in Marine City
Every plant below cleared Marine City's own zone 6a and its 207-day season. Each card opens that plant's Michigan profile. How we score.
Is it too late to plant in Marine City?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Mar 17; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 14 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 7 — long-season crops need about 90 days of runway, quick greens only 30. A long window like this one runs successions deep into fall — and even its last weeks take quick greens and garlic.
Documented around Marine City
Survey cells within 31 miles of Marine City checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 41 miles off. What to watch for.
What's on the federal record near Marine City
Closest first, within ~10 miles of Marine City. Listing isn't leaking, and distance isn't exposure.
- Detroit GasketUnderground Storage Tanks · 550 ft
- Marine City DpwUnderground Storage Tanks · 650 ft
- Sunrise Store #18Underground Storage Tanks · 650 ft
- SHELL OIL COMPANYBrownfields · 1100 ft
- Marine City MobilUnderground Storage Tanks · 1100 ft
- Lumberjack Bldg. Ctrs., IncUnderground Storage Tanks · 1800 ft
- C AND B ENTERPRISESToxics Release Inventory · 1900 ft
- Marine City Fire DeptUnderground Storage Tanks · 1900 ft
- MICHIGAN BELL TELEPHONE COMPANYBrownfields · 1900 ft
- Marine City GarageUnderground Storage Tanks · 1900 ft
- INTELLICHEM LLCBrownfields · 1900 ft
- Beauvais OilUnderground Storage Tanks · 2000 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Marine City'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 Marine City.
Total Sites
254
within ~10 miles of Marine City
Risk Level
Elevated
Highest-severity
2 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Marine City
Severity Distribution
within ~10 miles of Marine City
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Marine City, PFAS runs higher than the national average — 4 sites within ~10 miles of Marine City. It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Check your specific parcel in Marine City
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 Marine City average
Your land is one point inside Marine City
Everything above resolves to Marine City as a whole — one PHZM band and one 28°F frost record, read across 1K 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 Marine City Average
Marine City Average
- ●USDA Zones 6a, averaged across Marine City
- ●One soil character for all of Marine City
- ●Frost dates read at Marine City's scale: Apr 14 to Nov 7
YOUR Parcel
- ✓Your exact zone, not Marine City's 6a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Marine City
Pull a site-specific report for your exact address in Marine City, Michigan — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Marine City averages can't show:
We read public map data around Marine City — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Marine City average
How we know this about Marine City
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 Marine City’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 Marine City
When does frost risk typically end in Marine City?
The last hard freeze (28°F) in Marine City typically lands around Apr 14, 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 5.
When is the first frost in Marine City?
The first hard freeze (28°F) in Marine City typically arrives around Nov 7, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 24, so the watching starts about Oct 8 — about 207 days after the spring freeze cleared.
How long is the growing season in Marine City?
Measured between 28°F hard freezes, Marine City sees about 207 frost-free days — roughly Apr 14 through Nov 7, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 5 to Oct 24, about 172 days.
Is the soil safe to grow vegetables in Marine City?
The federal record around Marine City is a meaningful one — 254 documented sites, mostly Underground Storage Tanks entries (139), the nearest Underground Storage Tanks record about 0.1 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 Marine City?
From about Oct 8 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 7 (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 7. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Marine City's scale — its 6a band and its 207-day season. Your yard writes its own version of Marine City'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 Marine City’s own scale
7 of the readings below were taken at Marine City's own scale — its own ~207-day season between 28°F freezes, the 1,380 acres it covers and 254 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Marine City's own USDA hardiness band, zones 6aUSDA PHZM 2023
- Marine City's own 28°F hard-freeze dates, about Apr 14 and Nov 7 and the ~207-day span between themNOAA 1991–2020 Climate Normals
- 254 documented contamination sites on the federal record near Marine City, the closest Underground Storage Tanks record about 0.1 miles out from the town centreFederal environmental registers
- Marine City's boundary and the 1,380 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6a and a ~207-day seasonGrowable Ground crop-matching engine
- The ecoregion at Marine City's own centroid, the Huron/Erie Lake PlainsUS EPA Level III Ecoregions
- Lanternfly survey cells around Marine City checked, none carrying a detectionlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so Marine City's 1,380 acres read through its county's SSURGO summaryfrom St. Clair County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom St. Clair County
- The growing challenges every Michigan grower plans around — written at state scale, so they stay on the state guidefrom Michigan
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom St. Clair County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Marine City's 1,380 acreswhy one lot differs from the next →
- Which side of Marine City you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 1,380 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks 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 Marine City-wide figureread your own land →
More in Michigan
Wider growing context
What grows across MichiganMarine City sits outside our named growing regions, so Michigan as a whole is its closest context here.
Nearby growing guides