Arenac County, in Michigan, 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.
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.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Arenac County holds more than one microclimate.
Soils and elevations shift across Arenac County, so your frost dates and drainage aren't the county average. 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 Arenac County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Arenac County — the short answer
Arenac County, Michigan: USDA zone 6a, about 186 days between hard freezes, across 232K acres.
- USDA zone
- 6a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 21
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Oct 24
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~186
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 232K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are county 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 Arenac County's average, not your lot's — a low corner or a tree line moves it. Against Arenac County's 186-day season, see what your own ground reads.
Heat in Arenac County
Across a year, Arenac County accumulates about 2,117 growing degree days above 50°F, about 17 more than the middle Michigan county — ahead of 42 of Michigan’s 83 counties. Degree days are the heat a crop actually gets to work with — more of them is more room to ripen a long-season crop before the freeze closes the window.
Grounded in PRISM Climate Group, Oregon State University — 1991–2020 monthly normals
Soil in Arenac County
Across Arenac County, the ground is predominantly Spodosols, where Roscommon, Au Gres, and Rubicon are the most extensive named soil series. The soil is generally poorly drained with a sand surface. Topsoil pH runs about 5.8–6.7, slightly acidic. Rainfall drains through hydrologic group C/D soils.
Soil order
Spodosols
Drainage
Poorly drained
Prime farmland
8%
Hydric soils
44%
Soil still varies lot by lot — soil types explained.
How the ground varies across Arenac County
The USDA soil survey maps 35% of Arenac County as poorly drained — but another 63% drains differently: 31% somewhat poorly drained, 13% excessively drained.
Roscommon is the most extensive named soil at 10% of mapped acres, then Au Gres (7%) and Rubicon (6%).
Which of them your own lot sits on is a parcel question, not a county one. Check your address for the survey at your boundary.
What this means for growing in Arenac County
Each reading below is measured for Arenac County itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Drainage
MeasuredThe dominant soils across Arenac County are poorly drained, in hydrologic group C/D — ground that sheds water slowly.
Beds can stay saturated for days after heavy rain, and the roots of most vegetables, berries, and fruit trees suffocate or rot in soil that never drains.
Raised beds or mounded rows lift roots above the wet zone; choose water-tolerant crops for the lowest spots.
USDA NRCS SSURGO
Surface pH
MeasuredTopsoil across Arenac County runs about pH 5.8–6.7, close to neutral.
This is the range most vegetables prefer — one correction you probably do not have to make, which is genuinely good news for a new bed.
Keep it there with compost rather than lime or sulfur, and only amend if your own soil test says otherwise.
USDA NRCS SSURGO
Season length
MeasuredArenac County 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
MeasuredArenac County 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 Arenac County is in
Arenac County spans 2 EPA Level III ecoregions — Northern Lakes and Forests (91%) and Huron/Erie Lake Plains (9%). Which one your land falls in changes what grows wild there and how the ground behaves, and a county-wide answer cannot tell you which.
What Grows in Arenac County
We scored all 1,086 plants against Arenac County's own USDA zone 6a and its own 186-day season between hard freezes, using the same matching engine that runs a full parcel report. These cleared both. Sun, soil pH and drainage vary lot by lot — those are the parcel questions below. Each card opens that plant's Michigan profile.
Is it too late to plant in Arenac County?
Almost never — the real question is what to plant next. 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 Arenac County
- Japanese beetle1 documented records
- monarch butterfly2 documented records
Sighting records, so they follow observers as much as insects.
What gets applied to farmland in Arenac County
USGS estimates 57,048 lb of Glyphosate on Arenac County farmland in 2019, its largest by weight, ahead of Metolachlor & Metolachlor-s (13,173 lb) and Metolachlor-s (11,163 lb).
Farmland across the whole county, not any one lot. Check your address for the site-by-site record.
Safe to Grow Here?
What the federal record shows across Arenac County — and how to grow with it.
We checked the federal record across Arenac County — 156 documented sites across 5 of the 9 source types we track.
The most significant on record: 3 Toxics Release Inventory facilities. Active industrial facilities reporting chemical releases to air, water, and land.
The federal record across Arenac County is a modest one — a typical footprint for a growing area. Nothing here calls for alarm; it's worth knowing which recorded sites sit closest to where you grow, and each one on the map carries its type and location. If one turns out to be a near neighbor, a one-time soil test settles the question.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
What's on the federal record near Arenac County
Closest first, across Arenac County. Listing isn't leaking, and distance isn't exposure.
- Pier 23Underground Storage Tanks · 1.9 mi
- 4 Seasons Sport CenterUnderground Storage Tanks · 2.0 mi
- 140 S. Court St.Underground Storage Tanks · 2.3 mi
- Dewalds Shell ServiceUnderground Storage Tanks · 2.4 mi
- MI DEPT/TRANSPORTATION BRIDGE (B02-06073)Brownfields · 2.5 mi
- ATD ENGINEERING AND MACHINEBrownfields · 2.5 mi
- BOPP BUSCH MFG COBrownfields · 2.6 mi
- Former Pressler ElectricUnderground Storage Tanks · 2.6 mi
- Au Gres Yacht Club Marine StoreUnderground Storage Tanks · 2.6 mi
- Au Gres State DocksUnderground Storage Tanks · 2.6 mi
- River's Edge of Au Gres Inc (Lessee)Underground Storage Tanks · 2.7 mi
- Bopp-busch Mfg. CoUnderground Storage Tanks · 2.8 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Arenac County'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 Arenac County.
Total Sites
156
across Arenac County
Risk Level
Moderate
Highest-severity
3 Toxics Release Inventory facilities
Sources Checked
across Arenac County
Severity Distribution
across Arenac County
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 Arenac County
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 Arenac County average
Your land is one point inside Arenac County
Everything above resolves to Arenac County as a whole — one PHZM band and one county frost record, read across 232K 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 county 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 county average.
Your Lot vs the Arenac County Average
Arenac County Average
- ●USDA Zones 6a, averaged across Arenac County
- ●One soil character for all of Arenac County
- ●Frost dates read at Arenac County's scale: Apr 21 to Oct 24
YOUR Parcel
- ✓Your exact zone, not Arenac County's 6a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Arenac County
Pull a site-specific report for your exact address in Arenac County, Michigan — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Arenac County averages can't show:
We read public map data around Arenac County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Arenac County average
How we know this about Arenac County
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at county grain; hard-freeze dates from NOAA 1991–2020 28°F normals at this county’s own record where one resolves, and the labelled statewide window where none does; soils from the USDA NRCS SSURGO survey, area-weighted across the county’s own map units; boundaries and acreage from US Census TIGER/Line 2025; the contamination and pesticide records from the federal sources named in their beats above. Where Arenac County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Arenac County
When does frost risk typically end in Arenac County?
The last hard freeze (28°F) in Arenac County 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.
How long is the growing season in Arenac County?
Measured between 28°F hard freezes, Arenac County 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 Arenac County?
The federal record around Arenac County shows 156 documented sites, mostly Underground Storage Tanks entries (92), the nearest Underground Storage Tanks record about 1.9 miles out — a typical footprint for a growing area, and proximity to a documented site is information, not a diagnosis of any one yard. It's worth seeing which recorded sites sit closest to where you grow, and testing the soil before new food beds near any of them.
Everything above is measured at Arenac County's scale — its 6a band and its 186-day season. Your yard writes its own version of Arenac County's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
Will It Grow Here?
Zone fit is the first question — each answer below reads Michigan's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at Arenac County’s own scale
9 of the readings below were taken at Arenac County's own scale — its own ~186-day span between 28°F freezes, the 3 most extensive soil series mapped here and 156 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Arenac County's own USDA hardiness band, zones 6aUSDA PHZM 2023
- Arenac County's own 28°F hard-freeze dates and its ~186-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Arenac CountyUSDA NRCS SSURGO
- 156 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Underground Storage Tanks record about 1.9 miles outFederal environmental registers
- Arenac County's boundary and the 232,434 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 2 ecoregions Arenac County spans, Northern Lakes and Forests the largestUS EPA Level III Ecoregions
- Open occurrence records documented in Arenac County for 2 tracked speciesGBIF derived datasets (CC0 / CC BY 4.0)
- Which agricultural compounds go onto Arenac County farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every Michigan grower plans around — written at state scale, so they stay on the state guidefrom Michigan
What this page can’t tell you
- How the season shifts across Arenac County — the ~186 days above is one reading at its centre; the 12 towns below each carry their owntowns in this county →
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Arenac County's 232,434 acreswhy one lot differs from the next →
- Which of those 156 documented sites actually reaches your soil — that needs your address, the wind, and the groundwater directionhow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — none of it survives being averaged over Arenac Countyread your own land →