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

Planting zone for 49673 — Old Mission, MI

ZIP code 49673 (Old Mission, Grand Traverse County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is May 13 and the first fall frost October 19.

Where ZIP 49673 is

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.

Zone6b−5 to 0 °F

Coldest night−20.6 to −17.8 °C

Last frostMay 13

First frostOct 19

2012 zone6a

Was 6a 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 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Old Mission, 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 Old Mission, MI

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMay 13median — 50% chance of a later frost

Safe for tender plantsMay 29only 10% chance of frost after

First fall frostOctober 19median — 10% chance by Oct 1

Growing season158 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 30 and returns around November 4.

From the NOAA station Old Mission 3ssw, MI — 2 miles away, elevation 656 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 49673

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Apr 1 – Apr 15

SpinachSow outdoors · Apr 1 – Apr 22

Broccoli, cabbageStart indoors · Mar 4 – Mar 18

Broccoli, cabbageTransplant · Apr 22 – May 6

Onion setsPlant outdoors · Apr 15 – Apr 29

PotatoesPlant outdoors · Apr 22 – May 6

LettuceSow outdoors · Apr 15 – Apr 29

Carrots, beetsSow outdoors · Apr 22 – May 6

TomatoesStart indoors · Mar 18 – Apr 1

TomatoesTransplant · May 20 – Jun 3

Peppers, eggplantStart indoors · Mar 4 – Mar 18

Peppers, eggplantTransplant · May 27 – Jun 10

BeansSow outdoors · May 20 – Jun 3

Sweet cornSow outdoors · May 20 – Jun 3

Cucumbers, squashSow outdoors · May 20 – Jun 3

Fall lettuce, spinachSow outdoors · Aug 24 – Sep 7

GarlicPlant cloves · Oct 5 – Nov 9

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 13) and first fall frost (Oct 19) 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 49673 came on Apr 18 — 4 days earlier than the 1991–2020 average (Apr 22).

average
Apr 222026
Apr 18

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 6b in Michigan

582 plants native to the lower 48 states, recorded in Michigan, and rated by the USDA to survive −5 °F or colder — the bottom of zone 6b. 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 Old Mission, MI.

Soil in Old Mission, MI

The soil mapped at the center of ZIP 49673 is Emmet — sandy loam, well drained.

TextureSandy loamdrains and warms fast; dries out and needs more feeding

pH6.1slightly acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter2%moderate

Hydrologic groupBwater soaks in moderately

Farmland classFarmland of local importanceUSDA classification

Map unit: Emmet sandy loam, 6 to 12 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 49673; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Old Mission, MI

Summer high80 °Faverage high, July

Winter low16 °Faverage low, February

Hot days5days a year at 90 °F or more

Freezing nights157nights a year at 32 °F or less

Growing degree days2,248base 50 °F — the season’s usable heat

Longest day15 h 37 mindaylight on June 21

Shortest day8 h 46 mindaylight on December 21

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

Precipitation31.3 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: Old Mission 3ssw, MI (2 mi away); precipitation: Old Mission 3ssw, MI (2 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.

496296a

Elk Rapids, MI · 6 mi

496866b

Traverse City, MI · 8 mi

496486a

Kewadin, MI · 8 mi

496826b

Suttons Bay, MI · 8 mi

496746b

Omena, MI · 8 mi

496536b

Lake Leelanau, MI · 12 mi

496106a

Acme, MI · 12 mi

496766a

Rapid City, MI · 12 mi

Michigan planting zones →

Questions about 49673

What planting zone is ZIP code 49673?

ZIP code 49673 (Old Mission, MI) is in USDA hardiness zone 6b on the 2023 map: the coldest night of an average winter reaches −5 to 0 °F (−20.6 to −17.8 °C).

When is the last frost in Old Mission, MI?

The median last spring frost (32 °F) near 49673 is May 13; after May 29 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Old Mission 3ssw station.

When is the first frost in Old Mission, MI?

The median first fall frost near 49673 is October 19, giving a median frost-free growing season of 158 days.

When should I plant tomatoes in 49673?

Start tomato seeds indoors around Mar 18 – Apr 1 and set transplants outside around May 20 – Jun 3, one to three weeks after the median last frost.

How much rain and snow does 49673 get?

About 31.3 inches of precipitation a year (NOAA 1991–2020 normals, Old Mission 3ssw station).

How hot do summers get in Old Mission, MI?

The average high peaks at 80 °F in July, with about 5 days a year at 90 °F or more.

What kind of soil does 49673 have?

The USDA soil survey maps Emmet at the center of ZIP 49673: sandy loam, well drained, pH about 6.1 (slightly acidic).

Did spring come early in Old Mission, MI in 2026?

Spring leaf-out near 49673 came on Apr 18 in 2026, 4 days earlier than the 1991–2020 average (Apr 22), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Old Mission, MI?

Long-day onions: the longest day near 49673 is 15 h 37 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 49673 change?

Yes. The 2012 USDA map put 49673 in zone 6a; the 2023 map puts it in zone 6b. The newer map uses 1991–2020 data and more weather stations.