Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 48437 — Genesee, MI

ZIP code 48437 (Genesee, Genesee County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is May 8 and the first fall frost October 5.

Where ZIP 48437 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 8

First frostOct 5

2012 zone6a

Same zone as on the 2012 map. 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 Genesee, 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 Genesee, MI

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostMay 8median — 50% chance of a later frost

Safe for tender plantsMay 22only 10% chance of frost after

First fall frostOctober 5median — 10% chance by Sep 22

Growing season148 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 29 and returns around October 19.

From the NOAA station Burton 4n, MI — 4 miles away, elevation 758 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 48437

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 27 – Apr 10

SpinachSow outdoors · Mar 27 – Apr 17

Broccoli, cabbageStart indoors · Feb 27 – Mar 13

Broccoli, cabbageTransplant · Apr 17 – May 1

Onion setsPlant outdoors · Apr 10 – Apr 24

PotatoesPlant outdoors · Apr 17 – May 1

LettuceSow outdoors · Apr 10 – Apr 24

Carrots, beetsSow outdoors · Apr 17 – May 1

TomatoesStart indoors · Mar 13 – Mar 27

TomatoesTransplant · May 15 – May 29

Peppers, eggplantStart indoors · Feb 27 – Mar 13

Peppers, eggplantTransplant · May 22 – Jun 5

BeansSow outdoors · May 15 – May 29

Sweet cornSow outdoors · May 15 – May 29

Cucumbers, squashSow outdoors · May 15 – May 29

Fall lettuce, spinachSow outdoors · Aug 10 – Aug 24

GarlicPlant cloves · Sep 21 – Oct 26

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 8) and first fall frost (Oct 5) 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 48437 came on Apr 4 — 8 days earlier than the 1991–2020 average (Apr 12).

average
Apr 122026
Apr 4

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.

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 Genesee, MI.

Soil in Genesee, MI

The soil mapped at the center of ZIP 48437 is Tuscola — silt loam, moderately well drained.

TextureSilt loama good balance for most vegetables

pH7.0neutral; most vegetables like 6.0–7.0

DrainageModerately well drainednatural drainage class

Organic matter3%moderate

Hydrologic groupBwater soaks in moderately

Farmland classprime farmlandUSDA classification

Map unit: Tuscola silt loam, 0 to 2 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 48437; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Genesee, MI

Summer high84 °Faverage high, July

Winter low14 °Faverage low, February

Hot days15days a year at 90 °F or more

Freezing nights159nights a year at 32 °F or less

Growing degree days2,488base 50 °F — the season’s usable heat

Longest day15 h 23 mindaylight on June 21

Shortest day8 h 59 mindaylight on December 21

Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)

Precipitation34.5 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Burton 4n, MI (4 mi away); precipitation: Burton 4n, MI (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6a.

485066a

Flint, MI · 3 mi

484586a

Mount Morris, MI · 3 mi

Michigan planting zones →

Questions about 48437

What planting zone is ZIP code 48437?

ZIP code 48437 (Genesee, 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 Genesee, MI?

The median last spring frost (32 °F) near 48437 is May 8; after May 22 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Burton 4n station.

When is the first frost in Genesee, MI?

The median first fall frost near 48437 is October 5, giving a median frost-free growing season of 148 days.

When should I plant tomatoes in 48437?

Start tomato seeds indoors around Mar 13 – Mar 27 and set transplants outside around May 15 – May 29, one to three weeks after the median last frost.

How much rain and snow does 48437 get?

About 34.5 inches of precipitation a year (NOAA 1991–2020 normals, Burton 4n station).

How hot do summers get in Genesee, MI?

The average high peaks at 84 °F in July, with about 15 days a year at 90 °F or more.

What kind of soil does 48437 have?

The USDA soil survey maps Tuscola at the center of ZIP 48437: silt loam, moderately well drained, pH about 7.0 (neutral).

Did spring come early in Genesee, MI in 2026?

Spring leaf-out near 48437 came on Apr 4 in 2026, 8 days earlier than the 1991–2020 average (Apr 12), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Genesee, MI?

Long-day onions: the longest day near 48437 is 15 h 23 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).