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

Planting zone for 48624 — Gladwin, MI

ZIP code 48624 (Gladwin, Gladwin County) is in USDA zone 5b: the coldest winter night averages −15 to −10 °F. The median last spring frost is May 9 and the first fall frost October 4.

Where ZIP 48624 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.

Zone5b−15 to −10 °F
Coldest night−26.1 to −23.3 °C
Last frostMay 9
First frostOct 4
2012 zone5a

Was 5a 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 5b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Gladwin, 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 Gladwin, MI

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 9median — 50% chance of a later frost
Safe for tender plantsMay 23only 10% chance of frost after
First fall frostOctober 4median — 10% chance by Sep 22
Growing season148 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 30 and returns around October 17.

From the NOAA station Gladwin, MI — 6 miles away, elevation 774 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 48624

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 28 – Apr 11
SpinachSow outdoors · Mar 28 – Apr 18
Broccoli, cabbageStart indoors · Feb 28 – Mar 14
Broccoli, cabbageTransplant · Apr 18 – May 2
Onion setsPlant outdoors · Apr 11 – Apr 25
PotatoesPlant outdoors · Apr 18 – May 2
LettuceSow outdoors · Apr 11 – Apr 25
Carrots, beetsSow outdoors · Apr 18 – May 2
TomatoesStart indoors · Mar 14 – Mar 28
TomatoesTransplant · May 16 – May 30
Peppers, eggplantStart indoors · Feb 28 – Mar 14
Peppers, eggplantTransplant · May 23 – Jun 6
BeansSow outdoors · May 16 – May 30
Sweet cornSow outdoors · May 16 – May 30
Cucumbers, squashSow outdoors · May 16 – May 30
Fall lettuce, spinachSow outdoors · Aug 9 – Aug 23
GarlicPlant cloves · Sep 20 – Oct 25
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 9) and first fall frost (Oct 4) 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 48624 came on Apr 15 — about the same time as the 1991–2020 average (Apr 17).

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 5b in Michigan

564 plants native to the lower 48 states, recorded in Michigan, and rated by the USDA to survive −15 °F or colder — the bottom of zone 5b. Each links to its USDA PLANTS profile.

Trees 58

Shrubs 103

Wildflowers & perennials 212

Grasses 170

Vines 7

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 Gladwin, MI.

Soil in Gladwin, MI

The soil mapped at the center of ZIP 48624 is Montcalm — slightly decomposed plant material, well drained.

TextureSlightly decomposed plant materialtop layer
DrainageWell drainednatural drainage class
Organic matter85%high
Hydrologic groupAwater soaks in fast
Farmland classFarmland of local importanceUSDA classification

Map unit: Montcalm loamy sand, 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 48624; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Gladwin, MI

Summer high82 °Faverage high, July
Winter low13 °Faverage low, January
Hot days8days a year at 90 °F or more
Freezing nights165nights a year at 32 °F or less
Growing degree days2,274base 50 °F — the season’s usable heat
Longest day15 h 30 mindaylight on June 21
Shortest day8 h 53 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation34 inper year, rain and melted snow
Snowfall49 inper year; 91 days with snow on the ground

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 43 °F, low 20 °F 43°20° MarApril: average high 56 °F, low 31 °F 56°31° AprMay: average high 68 °F, low 43 °F 68°43° MayJune: average high 78 °F, low 53 °F 78°53° JunJuly: average high 82 °F, low 57 °F 82°57° JulAugust: average high 80 °F, low 55 °F 80°55° AugSeptember: average high 73 °F, low 47 °F 73°47° SepOctober: average high 60 °F, low 37 °F 60°37° OctNovember: average high 46 °F, low 28 °F 46°28° NovDecember: average high 34 °F, low 20 °F 34°20° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″January: 2.15 in precipitation, 13.8 in snowfall 2.1❄14 JanFebruary: 1.70 in precipitation, 11.4 in snowfall 1.7❄11 FebMarch: 2.05 in precipitation, 6.7 in snowfall 2.0❄7 MarApril: 3.53 in precipitation, 2.8 in snowfall 3.5❄3 AprMay: 3.78 in precipitation 3.8 MayJune: 3.46 in precipitation 3.5 JunJuly: 3.20 in precipitation 3.2 JulAugust: 3.39 in precipitation 3.4 AugSeptember: 2.79 in precipitation 2.8 SepOctober: 3.24 in precipitation, 0.4 in snowfall 3.2 OctNovember: 2.53 in precipitation, 2.8 in snowfall 2.5❄3 NovDecember: 2.20 in precipitation, 10.6 in snowfall 2.2❄11 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Gladwin, MI (6 mi away); precipitation: Gladwin, MI (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

4 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

Michigan planting zones →

Questions about 48624

What planting zone is ZIP code 48624?

ZIP code 48624 (Gladwin, MI) is in USDA hardiness zone 5b on the 2023 map: the coldest night of an average winter reaches −15 to −10 °F (−26.1 to −23.3 °C).

When is the last frost in Gladwin, MI?

The median last spring frost (32 °F) near 48624 is May 9; after May 23 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Gladwin station.

When is the first frost in Gladwin, MI?

The median first fall frost near 48624 is October 4, giving a median frost-free growing season of 148 days.

When should I plant tomatoes in 48624?

Start tomato seeds indoors around Mar 14 – Mar 28 and set transplants outside around May 16 – May 30, one to three weeks after the median last frost.

How much rain and snow does 48624 get?

About 34 inches of precipitation a year and 49 inches of snowfall (NOAA 1991–2020 normals, Gladwin station).

How hot do summers get in Gladwin, MI?

The average high peaks at 82 °F in July, with about 8 days a year at 90 °F or more.

What kind of soil does 48624 have?

The USDA soil survey maps Montcalm at the center of ZIP 48624: slightly decomposed plant material, well drained.

Did spring come early in Gladwin, MI in 2026?

Spring leaf-out near 48624 came on Apr 15 in 2026, about the same as the 1991–2020 average (Apr 17), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Gladwin, MI?

Long-day onions: the longest day near 48624 is 15 h 30 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 48624 change?

Yes. The 2012 USDA map put 48624 in zone 5a; the 2023 map puts it in zone 5b. The newer map uses 1991–2020 data and more weather stations.