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

Planting zone for 49420 — Hart, MI

ZIP code 49420 (Hart, Oceana County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is May 12 and the first fall frost October 10.

Where ZIP 49420 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 12
First frostOct 10
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 Hart, 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 Hart, MI

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 12median — 50% chance of a later frost
Safe for tender plantsMay 28only 10% chance of frost after
First fall frostOctober 10median — 10% chance by Sep 25
Growing season151 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 30 and returns around October 25.

From the NOAA station Hart 3 Wsw, MI — 7 miles away, elevation 771 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 49420

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 31 – Apr 14
SpinachSow outdoors · Mar 31 – Apr 21
Broccoli, cabbageStart indoors · Mar 3 – Mar 17
Broccoli, cabbageTransplant · Apr 21 – May 5
Onion setsPlant outdoors · Apr 14 – Apr 28
PotatoesPlant outdoors · Apr 21 – May 5
LettuceSow outdoors · Apr 14 – Apr 28
Carrots, beetsSow outdoors · Apr 21 – May 5
TomatoesStart indoors · Mar 17 – Mar 31
TomatoesTransplant · May 19 – Jun 2
Peppers, eggplantStart indoors · Mar 3 – Mar 17
Peppers, eggplantTransplant · May 26 – Jun 9
BeansSow outdoors · May 19 – Jun 2
Sweet cornSow outdoors · May 19 – Jun 2
Cucumbers, squashSow outdoors · May 19 – Jun 2
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 12) 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 49420 came on Apr 11 — 5 days earlier than the 1991–2020 average (Apr 16).

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 Hart, MI.

Soil in Hart, MI

The soil mapped at the center of ZIP 49420 is Pipestone — fine sand, somewhat poorly drained.

TextureFine sanddrains and warms fast; dries out and needs more feeding
pH4.7strongly acidic; most vegetables like 6.0–7.0
DrainageSomewhat poorly drainedconsider raised beds
Organic matter6.2%high
Hydrologic groupA/Ddrains fast once dried out; wet otherwise
Farmland classNot prime farmlandUSDA classification

Map unit: Pipestone fine sand, 0 to 4 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 49420; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Hart, MI

Summer high80 °Faverage high, July
Winter low16 °Faverage low, January
Hot days3days a year at 90 °F or more
Freezing nights151nights a year at 32 °F or less
Growing degree days2,267base 50 °F — the season’s usable heat
Longest day15 h 27 mindaylight on June 21
Shortest day8 h 55 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation38.9 inper year, rain and melted snow
Snowfall79 inper year; 82 days with snow on the ground

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 30 °F, low 16 °F 30°16° JanFebruary: average high 32 °F, low 16 °F 32°16° FebMarch: average high 42 °F, low 23 °F 42°23° MarApril: average high 55 °F, low 33 °F 55°33° AprMay: average high 67 °F, low 43 °F 67°43° MayJune: average high 76 °F, low 54 °F 76°54° JunJuly: average high 80 °F, low 58 °F 80°58° JulAugust: average high 79 °F, low 57 °F 79°57° AugSeptember: average high 72 °F, low 50 °F 72°50° SepOctober: average high 59 °F, low 39 °F 59°39° OctNovember: average high 45 °F, low 30 °F 45°30° NovDecember: average high 35 °F, low 22 °F 35°22° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 2.75 in precipitation, 26.4 in snowfall 2.8❄26 JanFebruary: 1.96 in precipitation, 20 in snowfall 2.0❄20 FebMarch: 2.37 in precipitation, 5.9 in snowfall 2.4❄6 MarApril: 3.63 in precipitation, 1.1 in snowfall 3.6❄1 AprMay: 4.45 in precipitation 4.5 MayJune: 3.72 in precipitation 3.7 JunJuly: 3.53 in precipitation 3.5 JulAugust: 3.27 in precipitation 3.3 AugSeptember: 3.23 in precipitation 3.2 SepOctober: 3.96 in precipitation, 0.1 in snowfall 4.0 OctNovember: 3.43 in precipitation, 5.4 in snowfall 3.4❄5 NovDecember: 2.60 in precipitation, 19.6 in snowfall 2.6❄20 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Hart 3 Wsw, MI (7 mi away); precipitation: Hart 3 Wsw, MI (7 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.

494496b
Pentwater, MI · 7 mi
494556a
Shelby, MI · 9 mi
494595b
Walkerville, MI · 9 mi
494366b
Mears, MI · 10 mi
494466a
New Era, MI · 13 mi
494215b
Hesperia, MI · 14 mi
494056a
Custer, MI · 14 mi
494526a
Rothbury, MI · 14 mi

Michigan planting zones →

Questions about 49420

What planting zone is ZIP code 49420?

ZIP code 49420 (Hart, 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 Hart, MI?

The median last spring frost (32 °F) near 49420 is May 12; after May 28 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Hart 3 Wsw station.

When is the first frost in Hart, MI?

The median first fall frost near 49420 is October 10, giving a median frost-free growing season of 151 days.

When should I plant tomatoes in 49420?

Start tomato seeds indoors around Mar 17 – Mar 31 and set transplants outside around May 19 – Jun 2, one to three weeks after the median last frost.

How much rain and snow does 49420 get?

About 38.9 inches of precipitation a year and 79 inches of snowfall (NOAA 1991–2020 normals, Hart 3 Wsw station).

How hot do summers get in Hart, MI?

The average high peaks at 80 °F in July, with about 3 days a year at 90 °F or more.

What kind of soil does 49420 have?

The USDA soil survey maps Pipestone at the center of ZIP 49420: fine sand, somewhat poorly drained, pH about 4.7 (strongly acidic).

Did spring come early in Hart, MI in 2026?

Spring leaf-out near 49420 came on Apr 11 in 2026, 5 days earlier than the 1991–2020 average (Apr 16), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Hart, MI?

Long-day onions: the longest day near 49420 is 15 h 27 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).