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

Planting zone for 46544 — Mishawaka, IN

ZIP code 46544 (Mishawaka, St. Joseph County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is April 23 and the first fall frost October 23.

Where ZIP 46544 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 23
First frostOct 23
2012 zone5b

Was 5b 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 6a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Mishawaka, IN…

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 Mishawaka, IN

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 23median — 50% chance of a later frost
Safe for tender plantsMay 9only 10% chance of frost after
First fall frostOctober 23median — 10% chance by Oct 9
Growing season181 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 12 and returns around November 3.

From the NOAA station S Bend, IN — 9 miles away, elevation 709 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 46544

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 12 – Mar 26
SpinachSow outdoors · Mar 12 – Apr 2
Broccoli, cabbageStart indoors · Feb 12 – Feb 26
Broccoli, cabbageTransplant · Apr 2 – Apr 16
Onion setsPlant outdoors · Mar 26 – Apr 9
PotatoesPlant outdoors · Apr 2 – Apr 16
LettuceSow outdoors · Mar 26 – Apr 9
Carrots, beetsSow outdoors · Apr 2 – Apr 16
TomatoesStart indoors · Feb 26 – Mar 12
TomatoesTransplant · Apr 30 – May 14
Peppers, eggplantStart indoors · Feb 12 – Feb 26
Peppers, eggplantTransplant · May 7 – May 21
BeansSow outdoors · Apr 30 – May 14
Sweet cornSow outdoors · Apr 30 – May 14
Cucumbers, squashSow outdoors · Apr 30 – May 14
Fall lettuce, spinachSow outdoors · Aug 28 – Sep 11
GarlicPlant cloves · Oct 9 – Nov 13
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 23) and first fall frost (Oct 23) 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 46544 came on Mar 23 — 13 days earlier than the 1991–2020 average (Apr 5).

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 Indiana

558 plants native to the lower 48 states, recorded in Indiana, and rated by the USDA to survive −10 °F or colder — the bottom of zone 6a. Each links to its USDA PLANTS profile.

Trees 71

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 holly40 ft · blooms mid spring · low shade tolerance · to −20 °F

Wildflowers & perennials 200

American bur-reed3 ft · blooms indeterminate · medium shade tolerance · to −33 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °FAmerican licorice4 ft · blooms late spring · medium shade tolerance · to −38 °FAmerican lotus3 ft · blooms mid summer · high shade tolerance · to −36 °FAmerican pokeweed7 ft · blooms mid summer · low shade tolerance · to −33 °FAmerican speedwell0.8 ft · blooms mid summer · low shade tolerance · to −38 °F

Grasses 161

American 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 spikerush3 ft · blooms late spring · high shade tolerance · to −28 °FBebb's sedge3 ft · blooms late spring · low shade tolerance · to −38 °FBicknell's sedge3 ft · blooms late spring · low shade tolerance · to −38 °F

Vines 9

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °Fcatbird grape30 ft · blooms late spring · medium shade tolerance · to −13 °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 °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 Mishawaka, IN.

Soil in Mishawaka, IN

The soil mapped at the center of ZIP 46544 is Milford — silty clay loam, poorly drained.

TextureSilty clay loamholds water and nutrients; slow to drain and warm up
pH6.5neutral; most vegetables like 6.0–7.0
DrainagePoorly drainedconsider raised beds
Organic matter5%high
Hydrologic groupC/Dslow when drained; wet otherwise
Farmland classPrime farmland if drainedUSDA classification

Map unit: Milford silty clay loam, 0 to 1 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 46544; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Mishawaka, IN

Summer high83 °Faverage high, July
Winter low17 °Faverage low, January
Hot days17days a year at 90 °F or more
Freezing nights133nights a year at 32 °F or less
Growing degree days2,979base 50 °F — the season’s usable heat
Longest day15 h 12 mindaylight on June 21
Shortest day9 h 09 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
Snowfall50 inper year

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 32 °F, low 17 °F 32°17° JanFebruary: average high 35 °F, low 19 °F 35°19° FebMarch: average high 47 °F, low 27 °F 47°27° MarApril: average high 59 °F, low 38 °F 59°38° AprMay: average high 70 °F, low 50 °F 70°50° MayJune: average high 80 °F, low 59 °F 80°59° JunJuly: average high 83 °F, low 63 °F 83°63° JulAugust: average high 81 °F, low 61 °F 81°61° AugSeptember: average high 76 °F, low 54 °F 76°54° SepOctober: average high 63 °F, low 42 °F 63°42° OctNovember: average high 48 °F, low 32 °F 48°32° NovDecember: average high 37 °F, low 23 °F 37°23° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 2.61 in precipitation, 16.8 in snowfall 2.6❄17 JanFebruary: 2.35 in precipitation, 14.3 in snowfall 2.4❄14 FebMarch: 2.19 in precipitation, 4 in snowfall 2.2❄4 MarApril: 3.25 in precipitation, 1.3 in snowfall 3.3❄1 AprMay: 4.19 in precipitation 4.2 MayJune: 4.43 in precipitation 4.4 JunJuly: 4.24 in precipitation 4.2 JulAugust: 3.90 in precipitation 3.9 AugSeptember: 3.27 in precipitation 3.3 SepOctober: 3.69 in precipitation 3.7 OctNovember: 2.64 in precipitation, 4.1 in snowfall 2.6❄4 NovDecember: 2.12 in precipitation, 9.4 in snowfall 2.1❄9 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: S Bend, IN (9 mi away); precipitation: South Bend 4.6 Se, IN (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6a.

465466a
Mishawaka, IN · 4 mi
465616a
Osceola, IN · 5 mi
465456a
Mishawaka, IN · 5 mi
465736a
Wakarusa, IN · 6 mi
466156a
South Bend, IN · 6 mi
465956a
Wyatt, IN · 6 mi
465176a
Elkhart, IN · 7 mi
466176a
South Bend, IN · 7 mi

All 3 ZIP codes in Mishawaka → · Indiana planting zones →

Questions about 46544

What planting zone is ZIP code 46544?

ZIP code 46544 (Mishawaka, IN) 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 Mishawaka, IN?

The median last spring frost (32 °F) near 46544 is April 23; after May 9 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, S Bend station.

When is the first frost in Mishawaka, IN?

The median first fall frost near 46544 is October 23, giving a median frost-free growing season of 181 days.

When should I plant tomatoes in 46544?

Start tomato seeds indoors around Feb 26 – Mar 12 and set transplants outside around Apr 30 – May 14, one to three weeks after the median last frost.

How much rain and snow does 46544 get?

About 38.9 inches of precipitation a year and 50 inches of snowfall (NOAA 1991–2020 normals, South Bend 4.6 Se station).

How hot do summers get in Mishawaka, IN?

The average high peaks at 83 °F in July, with about 17 days a year at 90 °F or more.

What kind of soil does 46544 have?

The USDA soil survey maps Milford at the center of ZIP 46544: silty clay loam, poorly drained, pH about 6.5 (neutral).

Did spring come early in Mishawaka, IN in 2026?

Spring leaf-out near 46544 came on Mar 23 in 2026, 13 days earlier than the 1991–2020 average (Apr 5), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Mishawaka, IN?

Long-day onions: the longest day near 46544 is 15 h 12 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 46544 change?

Yes. The 2012 USDA map put 46544 in zone 5b; the 2023 map puts it in zone 6a. The newer map uses 1991–2020 data and more weather stations.