Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated

Planting zone for 48726 — Cass City, MI

ZIP code 48726 (Cass City, Tuscola County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is May 7 and the first fall frost October 10.

Where ZIP 48726 is

Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zone6a−10 to −5 °F
Coldest night−23.3 to −20.6 °C
Last frostMay 7
First frostOct 10
2012 zone5b

Was 5b on the 2012 map — half a zone warmer now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 6a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Cass City, MI…

Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates in Cass City, MI

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 7median — 50% chance of a later frost
Safe for tender plantsMay 22only 10% chance of frost after
First fall frostOctober 10median — 10% chance by Sep 26
Growing season152 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 28 and returns around October 24.

From the NOAA station Cass City 1 Ssw, MI — 2 miles away, elevation 699 ft. NOAA NCEI U.S. Climate Normals 1991–2020, 32 °F threshold. Low spots and valleys can freeze later in spring than the station.

When to plant vegetables in 48726

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 26 – Apr 9
SpinachSow outdoors · Mar 26 – Apr 16
Broccoli, cabbageStart indoors · Feb 26 – Mar 12
Broccoli, cabbageTransplant · Apr 16 – Apr 30
Onion setsPlant outdoors · Apr 9 – Apr 23
PotatoesPlant outdoors · Apr 16 – Apr 30
LettuceSow outdoors · Apr 9 – Apr 23
Carrots, beetsSow outdoors · Apr 16 – Apr 30
TomatoesStart indoors · Mar 12 – Mar 26
TomatoesTransplant · May 14 – May 28
Peppers, eggplantStart indoors · Feb 26 – Mar 12
Peppers, eggplantTransplant · May 21 – Jun 4
BeansSow outdoors · May 14 – May 28
Sweet cornSow outdoors · May 14 – May 28
Cucumbers, squashSow outdoors · May 14 – May 28
Fall lettuce, spinachSow outdoors · Aug 15 – Aug 29
GarlicPlant cloves · Sep 26 – Oct 31
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 7) and first fall frost (Oct 10) with the rules of thumb U.S. extension services publish. Cool-season crops take a light frost; warm-season crops do best once the soil is above about 60 °F.

When spring arrived in 2026

In 2026, spring leaf-out near 48726 came on Apr 15 — about the same time as the 1991–2020 average (Apr 15).

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Native plants for zone 6a in Michigan

580 plants native to the lower 48 states, recorded in Michigan, and rated by the USDA to survive −10 °F or colder — the bottom of zone 6a. Each links to its USDA PLANTS profile.

Trees 58

American basswood100 ft · blooms late spring · low shade tolerance · to −46 °FAmerican beech80 ft · blooms mid spring · low shade tolerance · to −44 °FAmerican chestnut115 ft · blooms early summer · high shade tolerance · to −33 °FAmerican elm120 ft · blooms early spring · medium shade tolerance · to −46 °FAmerican sycamore100 ft · blooms spring · medium shade tolerance · to −34 °Farborvitae50 ft · blooms mid spring · medium shade tolerance · to −33 °F

Shrubs 105

alderleaf buckthorn3 ft · blooms late spring · low shade tolerance · to −33 °FAllegheny serviceberry35 ft · blooms early spring · low shade tolerance · to −38 °Falternateleaf dogwood25 ft · blooms mid spring · low shade tolerance · to −47 °FAmerican black currant3 ft · blooms early spring · to −46 °FAmerican hazelnut10 ft · blooms spring · medium shade tolerance · to −33 °FAmerican hornbeam30 ft · blooms mid spring · low shade tolerance · to −34 °F

Wildflowers & perennials 220

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °Falpine bistort1 ft · blooms mid spring · high shade tolerance · to −38 °Falpine sweetvetch2 ft · blooms early summer · high shade tolerance · to −62 °FAmerican bur-reed3 ft · blooms indeterminate · medium shade tolerance · to −33 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °FAmerican lotus3 ft · blooms mid summer · high shade tolerance · to −36 °F

Grasses 174

alpine timothy1.4 ft · blooms late spring · medium shade tolerance · to −43 °FAmerican beachgrass2.5 ft · blooms spring · high shade tolerance · to −28 °Farctic brome3 ft · blooms early summer · low shade tolerance · to −33 °Fawlfruit sedge4 ft · blooms mid spring · low shade tolerance · to −38 °Fbeaked sedge4 ft · blooms late spring · low shade tolerance · to −38 °Fbeaked spikerush3 ft · blooms late spring · high shade tolerance · to −28 °F

Vines 8

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °Fdevil's darning needles15 ft · blooms mid summer · medium shade tolerance · to −38 °Ffrost grape83 ft · blooms late spring · medium shade tolerance · to −23 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °Fsummer grape30 ft · blooms late spring · low shade tolerance · to −23 °Ftrumpet creeper2 ft · blooms summer · high shade tolerance · to −13 °F

Source: USDA, NRCS. 2026. The PLANTS Database (plants.usda.gov), National Plant Data Team — state distribution, native status and the “Temperature, Minimum” characteristic. Check light, moisture and soil needs before buying; local nurseries and your state native plant society can confirm what thrives in Cass City, MI.

Soil in Cass City, MI

The soil mapped at the center of ZIP 48726 is Guelph — loam, moderately well drained.

TextureLoama good balance for most vegetables
pH7.6slightly alkaline; most vegetables like 6.0–7.0
DrainageModerately well drainednatural drainage class
Organic matter2.25%moderate
Hydrologic groupCwater soaks in slowly
Farmland classPrime farmland if drainedUSDA classification

Map unit: Guelph-Londo loams, 0 to 6 percent slopes.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 48726; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Cass City, MI

Summer high80 °Faverage high, July
Winter low13 °Faverage low, January
Hot days7days a year at 90 °F or more
Freezing nights158nights a year at 32 °F or less
Growing degree days2,263base 50 °F — the season’s usable heat
Longest day15 h 26 mindaylight on June 21
Shortest day8 h 56 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation33 inper year, rain and melted snow
Snowfall43 inper year

Average high and low, by month

0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 29 °F, low 13 °F 29°13° JanFebruary: average high 32 °F, low 13 °F 32°13° FebMarch: average high 42 °F, low 22 °F 42°22° MarApril: average high 55 °F, low 32 °F 55°32° AprMay: average high 68 °F, low 43 °F 68°43° MayJune: average high 77 °F, low 54 °F 77°54° JunJuly: average high 80 °F, low 57 °F 80°57° JulAugust: average high 79 °F, low 56 °F 79°56° AugSeptember: average high 72 °F, low 49 °F 72°49° SepOctober: average high 59 °F, low 39 °F 59°39° OctNovember: average high 45 °F, low 29 °F 45°29° NovDecember: average high 34 °F, low 21 °F 34°21° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″January: 2.02 in precipitation, 14.4 in snowfall 2.0❄14 JanFebruary: 1.79 in precipitation, 9.3 in snowfall 1.8❄9 FebMarch: 1.99 in precipitation, 5 in snowfall 2.0❄5 MarApril: 3.50 in precipitation, 1.6 in snowfall 3.5❄2 AprMay: 3.52 in precipitation 3.5 MayJune: 3.27 in precipitation 3.3 JunJuly: 3.24 in precipitation 3.2 JulAugust: 3.12 in precipitation 3.1 AugSeptember: 3.17 in precipitation 3.2 SepOctober: 2.91 in precipitation, 0.1 in snowfall 2.9 OctNovember: 2.52 in precipitation, 3.1 in snowfall 2.5❄3 NovDecember: 2.00 in precipitation, 9 in snowfall 2.0❄9 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Cass City 1 Ssw, MI (2 mi away); precipitation: Cass City 1 Ssw, MI (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6a.

487356a
Gagetown, MI · 7 mi
487296a
Deford, MI · 8 mi
484266a
Decker, MI · 9 mi
487546a
Owendale, MI · 9 mi
484106a
Argyle, MI · 12 mi
484726a
Snover, MI · 12 mi
484756a
Ubly, MI · 13 mi
487556a
Pigeon, MI · 13 mi

Michigan planting zones →

Questions about 48726

What planting zone is ZIP code 48726?

ZIP code 48726 (Cass City, MI) is in USDA hardiness zone 6a on the 2023 map: the coldest night of an average winter reaches −10 to −5 °F (−23.3 to −20.6 °C).

When is the last frost in Cass City, MI?

The median last spring frost (32 °F) near 48726 is May 7; after May 22 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Cass City 1 Ssw station.

When is the first frost in Cass City, MI?

The median first fall frost near 48726 is October 10, giving a median frost-free growing season of 152 days.

When should I plant tomatoes in 48726?

Start tomato seeds indoors around Mar 12 – Mar 26 and set transplants outside around May 14 – May 28, one to three weeks after the median last frost.

How much rain and snow does 48726 get?

About 33 inches of precipitation a year and 43 inches of snowfall (NOAA 1991–2020 normals, Cass City 1 Ssw station).

How hot do summers get in Cass City, MI?

The average high peaks at 80 °F in July, with about 7 days a year at 90 °F or more.

What kind of soil does 48726 have?

The USDA soil survey maps Guelph at the center of ZIP 48726: loam, moderately well drained, pH about 7.6 (slightly alkaline).

Did spring come early in Cass City, MI in 2026?

Spring leaf-out near 48726 came on Apr 15 in 2026, about the same as the 1991–2020 average (Apr 15), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Cass City, MI?

Long-day onions: the longest day near 48726 is 15 h 26 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 48726 change?

Yes. The 2012 USDA map put 48726 in zone 5b; the 2023 map puts it in zone 6a. The newer map uses 1991–2020 data and more weather stations.