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

Planting zone for 49128 — Three Oaks, MI

ZIP code 49128 (Three Oaks, Berrien County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is April 19 and the first fall frost October 27.

Where ZIP 49128 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 frostApr 19
First frostOct 27
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 Three Oaks, 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 Three Oaks, MI

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 19median — 50% chance of a later frost
Safe for tender plantsMay 3only 10% chance of frost after
First fall frostOctober 27median — 10% chance by Oct 14
Growing season191 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 7 and returns around November 7.

From the NOAA station Laporte, IN — 16 miles away, elevation 810 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 49128

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 8 – Mar 22
SpinachSow outdoors · Mar 8 – Mar 29
Broccoli, cabbageStart indoors · Feb 8 – Feb 22
Broccoli, cabbageTransplant · Mar 29 – Apr 12
Onion setsPlant outdoors · Mar 22 – Apr 5
PotatoesPlant outdoors · Mar 29 – Apr 12
LettuceSow outdoors · Mar 22 – Apr 5
Carrots, beetsSow outdoors · Mar 29 – Apr 12
TomatoesStart indoors · Feb 22 – Mar 8
TomatoesTransplant · Apr 26 – May 10
Peppers, eggplantStart indoors · Feb 8 – Feb 22
Peppers, eggplantTransplant · May 3 – May 17
BeansSow outdoors · Apr 26 – May 10
Sweet cornSow outdoors · Apr 26 – May 10
Cucumbers, squashSow outdoors · Apr 26 – May 10
Fall lettuce, spinachSow outdoors · Sep 1 – Sep 15
GarlicPlant cloves · Oct 13 – Nov 17
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 19) and first fall frost (Oct 27) 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 49128 came on Mar 23 — 14 days earlier than the 1991–2020 average (Apr 6).

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 Three Oaks, MI.

Soil in Three Oaks, MI

The soil mapped at the center of ZIP 49128 is Blount — loam, somewhat poorly drained.

TextureLoama good balance for most vegetables
pH6.7neutral; most vegetables like 6.0–7.0
DrainageSomewhat poorly drainedconsider raised beds
Organic matter2.5%moderate
Hydrologic groupC/Dslow when drained; wet otherwise
Farmland classPrime farmland if drainedUSDA classification

Map unit: Blount loam, 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 49128; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Three Oaks, MI

Summer high82 °Faverage high, July
Winter low17 °Faverage low, January
Hot days10days a year at 90 °F or more
Freezing nights119nights a year at 32 °F or less
Growing degree days3,052base 50 °F — the season’s usable heat
Longest day15 h 13 mindaylight on June 21
Shortest day9 h 08 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation42.6 inper year, rain and melted snow
Snowfall62 inper year

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 31 °F, low 17 °F 31°17° JanFebruary: average high 35 °F, low 20 °F 35°20° FebMarch: average high 46 °F, low 29 °F 46°29° MarApril: average high 59 °F, low 39 °F 59°39° AprMay: average high 70 °F, low 50 °F 70°50° MayJune: average high 79 °F, low 60 °F 79°60° JunJuly: average high 82 °F, low 64 °F 82°64° JulAugust: average high 80 °F, low 63 °F 80°63° AugSeptember: average high 74 °F, low 55 °F 74°55° SepOctober: average high 62 °F, low 44 °F 62°44° OctNovember: average high 48 °F, low 33 °F 48°33° NovDecember: average high 36 °F, low 24 °F 36°24° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 2.88 in precipitation, 22.4 in snowfall 2.9❄22 JanFebruary: 2.70 in precipitation, 17.8 in snowfall 2.7❄18 FebMarch: 2.83 in precipitation, 5 in snowfall 2.8❄5 MarApril: 3.74 in precipitation, 0.5 in snowfall 3.7❄1 AprMay: 4.41 in precipitation 4.4 MayJune: 4.56 in precipitation 4.6 JunJuly: 4.33 in precipitation 4.3 JulAugust: 4.12 in precipitation 4.1 AugSeptember: 3.16 in precipitation 3.2 SepOctober: 4.36 in precipitation, 0.2 in snowfall 4.4 OctNovember: 3.22 in precipitation, 5.5 in snowfall 3.2❄6 NovDecember: 2.32 in precipitation, 10.7 in snowfall 2.3❄11 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Laporte, IN (16 mi away); precipitation: New Carlisle, IN (9 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

491166b
Lakeside, MI · 4 mi
491156b
Harbert, MI · 4 mi
491296b
Union Pier, MI · 4 mi
491196a
New Troy, MI · 5 mi
491256b
Sawyer, MI · 5 mi
491136a
Galien, MI · 5 mi
491176a
New Buffalo, MI · 7 mi
491066b
Bridgman, MI · 8 mi

Michigan planting zones →

Questions about 49128

What planting zone is ZIP code 49128?

ZIP code 49128 (Three Oaks, 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 Three Oaks, MI?

The median last spring frost (32 °F) near 49128 is April 19; after May 3 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Laporte station.

When is the first frost in Three Oaks, MI?

The median first fall frost near 49128 is October 27, giving a median frost-free growing season of 191 days.

When should I plant tomatoes in 49128?

Start tomato seeds indoors around Feb 22 – Mar 8 and set transplants outside around Apr 26 – May 10, one to three weeks after the median last frost.

How much rain and snow does 49128 get?

About 42.6 inches of precipitation a year and 62 inches of snowfall (NOAA 1991–2020 normals, New Carlisle station).

How hot do summers get in Three Oaks, MI?

The average high peaks at 82 °F in July, with about 10 days a year at 90 °F or more.

What kind of soil does 49128 have?

The USDA soil survey maps Blount at the center of ZIP 49128: loam, somewhat poorly drained, pH about 6.7 (neutral).

Did spring come early in Three Oaks, MI in 2026?

Spring leaf-out near 49128 came on Mar 23 in 2026, 14 days earlier than the 1991–2020 average (Apr 6), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Three Oaks, MI?

Long-day onions: the longest day near 49128 is 15 h 13 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).