Rock, Michigan, sits in USDA hardiness zone 5a — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
Growers here do well with cabbage, cranberry, lavender, and collard greens — with the usual caveat that any single yard's soil, sun, and drainage cast the deciding vote.
Even in Rock, 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 Rock 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 Rock — soil, climate, flood, and parcel records. How we handle your address.
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Rock — the short answer
Rock, Michigan: USDA zone 5a, about 148 days between hard freezes, across 577 acres of town.
- USDA zone
- 5a
- USDA PHZM 2023
- Last hard freeze (28°F)
- May 11
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 6
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~148
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 577 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 5a is Rock's average, not your lot's — a low corner or a tree line moves it. Against Rock's 148-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Rock
Each reading below is measured for Rock itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredRock runs about 148 days between hard freezes — a short growing season.
Long-maturing crops like melons, sweet potatoes, and winter squash can run out of runway before the first hard freeze, ripening late or not at all.
Lead with fast-maturing varieties, and stretch the season on both ends with cold frames, low tunnels, or a greenhouse.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredRock sits in USDA hardiness zone 5a.
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 Rock is in
Rock sits in the Northern Lakes and Forests — EPA Level III, inside the wider Northern Forests. That is read at Rock's own centroid rather than borrowed from Delta County.
What Grows in Rock
Every plant below cleared Rock's own zone 5a and its 148-day season. Each card opens that plant's Michigan profile. How we score.
Is it too late to plant in Rock?
Too late for some crops, right on time for others — a growing season is a sequence, not a deadline. Cool-season crops can go in from around Apr 13; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near May 11 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 6 — long-season crops need about 90 days of runway, quick greens only 30. Short seasons reward decisiveness — quick-maturing varieties late, hardy greens under cover, and next year’s garlic in the ground before it closes.
What's on the federal record near Rock
Closest first, within ~10 miles of Rock. Listing isn't leaking, and distance isn't exposure.
- 42N 23W 03AA 01Nitrate · 100 ft
- Dcrc - Rock District GarageUnderground Storage Tanks · 250 ft
- Georges ServiceUnderground Storage Tanks · 950 ft
- Hansens GroceryUnderground Storage Tanks · 1000 ft
- Up FabricatingUnderground Storage Tanks · 1000 ft
- Joe's One StopUnderground Storage Tanks · 1000 ft
- U P TRACTOR INCBrownfields · 2100 ft
- UP FABRICATING CO INCBrownfields · 4.4 mi
- 42N 24W 02BC 01 MARQUETTE CO (HARKONEN)Nitrate · 5.7 mi
- 42N24W02BDB 01 LARSON, HNitrate · 5.7 mi
- 42N 24W 25BC 01 MARQUETTE CO (SEGAR)Nitrate · 6.2 mi
- 41N 22W 06BABB01 DELTA CO (MID-PENINSULA)Nitrate · Not nearby
6 more sites are on the record inside the same radius. See them on the map
Measured from Rock'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 Rock.
Severity Distribution
within ~10 miles of Rock
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Rock, Nitrate runs higher than the national average — 30 sites within ~10 miles of Rock. That's not a problem with your land — it's information about it.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in Rock
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 Rock average
Your land is one point inside Rock
Everything above resolves to Rock as a whole — one PHZM band and one 28°F frost record, read across 577 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 Rock Average
Rock Average
- ●USDA Zones 5a, averaged across Rock
- ●One soil character for all of Rock
- ●Frost dates read at Rock's scale: May 11 to Oct 6
YOUR Parcel
- ✓Your exact zone, not Rock's 5a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Rock
Pull a site-specific report for your exact address in Rock, Michigan — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Rock averages can't show:
We read public map data around Rock — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Rock average
How we know this about Rock
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 Rock’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 Rock
When does frost risk typically end in Rock?
The last hard freeze (28°F) in Rock typically lands around May 11, 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 Jun 1.
When is the first frost in Rock?
The first hard freeze (28°F) in Rock typically arrives around Oct 6, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 22, so the watching starts about Sep 6 — about 148 days after the spring freeze cleared.
How long is the growing season in Rock?
Measured between 28°F hard freezes, Rock sees about 148 frost-free days — roughly May 11 through Oct 6, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Jun 1 to Sep 22, about 113 days.
Is the soil safe to grow vegetables in Rock?
The federal record around Rock is light — 44 documented sites across the 9 federal source types we checked, mostly Nitrate entries (30), the nearest Nitrate record under a tenth of a mile out — and proximity to a documented site is information, not a diagnosis of any one yard. Growing food here starts from a strong position; a soil test before new food beds settles any site-specific question.
How do gardeners stretch the season in Rock?
With about 148 frost-free days between hard freezes, Rock rewards the classic extension moves: floating row cover buys roughly two to four extra weeks at each shoulder — on this season that is a working window nearer 176 to 204 days — and cold frames or low tunnels buy more. Starting transplants indoors ahead of the May 11 hard-freeze normal stretches the season without touching the calendar.
Everything above is measured at Rock's scale — its 5a band and its 148-day season. Your yard writes its own version of Rock'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 Rock’s own scale
6 of the readings below were taken at Rock's own scale — its own ~148-day season between 28°F freezes, the 577 acres it covers and 44 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Rock's own USDA hardiness band, zones 5aUSDA PHZM 2023
- Rock's own 28°F hard-freeze dates, about May 11 and Oct 6 and the ~148-day span between themNOAA 1991–2020 Climate Normals
- 44 documented contamination sites on the federal record near Rock, the closest Nitrate record under a tenth of a mile out from the town centreFederal environmental registers
- Rock's boundary and the 577 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5a and a ~148-day seasonGrowable Ground crop-matching engine
- The ecoregion at Rock's own centroid, the Northern Lakes and ForestsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Rock's 577 acres read through its county's SSURGO summaryfrom Delta County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Delta 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 Delta County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Rock's 577 acreswhy one lot differs from the next →
- Which side of Rock you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 577 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Nitrate record under a tenth of a mile 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 Rock-wide figureread your own land →
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