Napoleon, Michigan, sits in USDA hardiness zone 6a — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
A short list that earns its place here — cabbage, hazelnut, lavender, and collard greens — with any one site's soil, sun, and drainage making the final cut.
Even in Napoleon, 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 Napoleon 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 Napoleon — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Napoleon — the short answer
Napoleon, Michigan: USDA zone 6a, about 186 days between hard freezes, across 2K acres of town.
- USDA zone
- 6a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 21
- 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
- ~186
- 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 Napoleon's average, not your lot's — a low corner or a tree line moves it. Against Napoleon's 186-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Napoleon
Each reading below is measured for Napoleon itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredNapoleon runs about 186 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
MeasuredNapoleon 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 Napoleon is in
Napoleon sits in the Southern Michigan/Northern Indiana Drift Plains — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Napoleon's own centroid rather than borrowed from Jackson County.
What Grows in Napoleon
Every plant below cleared Napoleon's own zone 6a and its 186-day season. Each card opens that plant's Michigan profile. How we score.
Is it too late to plant in Napoleon?
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 24; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 21 (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. Even past midsummer there is room for a true fall garden here, and garlic planted near the close carries the momentum into next year.
Documented around Napoleon
Survey cells within 31 miles of Napoleon checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 44 miles off. What to watch for.
What's on the federal record near Napoleon
Closest first, within ~10 miles of Napoleon. Listing isn't leaking, and distance isn't exposure.
- TransportationUnderground Storage Tanks · 1400 ft
- NAPOLEON COMMUNITY SCHOOLSBrownfields · 1400 ft
- Eby Elementary SchoolUnderground Storage Tanks · 1400 ft
- Napoleon Twp Fire DeptUnderground Storage Tanks · 1500 ft
- Judes Stone QuarryUnderground Storage Tanks · 1600 ft
- ATLANTIC RICHFIELD COMPANYBrownfields · 1700 ft
- Express MartUnderground Storage Tanks · 1700 ft
- Napoleon Lumber CoUnderground Storage Tanks · 1700 ft
- B & B Food Mart LLCUnderground Storage Tanks · 1800 ft
- MI DEPT/TRANSPORTATIONBrownfields · 1900 ft
- Napoleon CollisionUnderground Storage Tanks · 2000 ft
- Robert ParmerUnderground Storage Tanks · 2300 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Napoleon'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 Napoleon.
Total Sites
500
within ~10 miles of Napoleon
Risk Level
Elevated
Highest-severity
6 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Napoleon
Severity Distribution
within ~10 miles of Napoleon
Highest-Severity Sites
Know Before You Grow
- •Underground tanks leak petroleum as they age — near a former filling station, test the soil.
- •Near a brownfield, raised beds of imported soil give your food clean ground.
- •On a private well, test for nitrates: above 10 mg/L the water needs treatment before irrigating.
Check your specific parcel in Napoleon
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 Napoleon average
Your land is one point inside Napoleon
Everything above resolves to Napoleon 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 Napoleon Average
Napoleon Average
- ●USDA Zones 6a, averaged across Napoleon
- ●One soil character for all of Napoleon
- ●Frost dates read at Napoleon's scale: Apr 21 to Oct 24
YOUR Parcel
- ✓Your exact zone, not Napoleon's 6a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Napoleon
Pull a site-specific report for your exact address in Napoleon, Michigan — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Napoleon averages can't show:
We read public map data around Napoleon — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Napoleon average
How we know this about Napoleon
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 Napoleon’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 Napoleon
When does frost risk typically end in Napoleon?
The last hard freeze (28°F) in Napoleon typically lands around Apr 21, 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 12.
When is the first frost in Napoleon?
The first hard freeze (28°F) in Napoleon 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 186 days after the spring freeze cleared.
How long is the growing season in Napoleon?
Measured between 28°F hard freezes, Napoleon sees about 186 frost-free days — roughly Apr 21 through Oct 24, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 12 to Oct 10, about 151 days.
Is the soil safe to grow vegetables in Napoleon?
The federal record around Napoleon is a meaningful one — 500 documented sites, mostly Underground Storage Tanks entries (262), the nearest Underground Storage Tanks 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 Napoleon?
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 Napoleon's scale — its 6a band and its 186-day season. Your yard writes its own version of Napoleon'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 Napoleon’s own scale
7 of the readings below were taken at Napoleon's own scale — its own ~186-day season between 28°F freezes, the 1,677 acres it covers and 500 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Napoleon's own USDA hardiness band, zones 6aUSDA PHZM 2023
- Napoleon's own 28°F hard-freeze dates, about Apr 21 and Oct 24 and the ~186-day span between themNOAA 1991–2020 Climate Normals
- 500 documented contamination sites on the federal record near Napoleon, the closest Underground Storage Tanks record about 0.3 miles out from the town centreFederal environmental registers
- Napoleon's boundary and the 1,677 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6a and a ~186-day seasonGrowable Ground crop-matching engine
- The ecoregion at Napoleon's own centroid, the Southern Michigan/Northern Indiana Drift PlainsUS EPA Level III Ecoregions
- Lanternfly survey cells around Napoleon 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 Napoleon's 1,677 acres read through its county's SSURGO summaryfrom Jackson County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Jackson 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 Jackson County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Napoleon's 1,677 acreswhy one lot differs from the next →
- Which side of Napoleon you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 1,677 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks 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 Napoleon-wide figureread your own land →
More in Michigan
Wider growing context
What grows across MichiganNapoleon sits outside our named growing regions, so Michigan as a whole is its closest context here.
Nearby growing guides