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

Planting zone for 46561 — Osceola, IN

ZIP code 46561 (Osceola, 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 46561 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 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 Osceola, 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 Osceola, 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 46561

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 46561 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 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

Shrubs 105

Wildflowers & perennials 200

Grasses 161

Vines 9

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 Osceola, IN.

Soil in Osceola, IN

The soil mapped at the center of ZIP 46561 is Tyner — loamy sand, excessively drained. Much of the area is built over (urban land); this is the natural soil underneath.

TextureLoamy sanddrains and warms fast; dries out and needs more feeding
pH5.9moderately acidic; most vegetables like 6.0–7.0
DrainageExcessively drainednatural drainage class
Organic matter1%low — add compost
Hydrologic groupAwater soaks in fast
Farmland classNot prime farmlandUSDA classification

Map unit: Urban land-Tyner complex, 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 46561; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Osceola, 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)
Precipitation39.1 inper year, rain and melted snow

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

0″1″2″3″4″5″January: 2.46 in precipitation 2.5 JanFebruary: 2.49 in precipitation 2.5 FebMarch: 2.35 in precipitation 2.4 MarApril: 3.38 in precipitation 3.4 AprMay: 4.10 in precipitation 4.1 MayJune: 4.19 in precipitation 4.2 JunJuly: 3.84 in precipitation 3.8 JulAugust: 4.21 in precipitation 4.2 AugSeptember: 3.28 in precipitation 3.3 SepOctober: 3.36 in precipitation 3.4 OctNovember: 2.91 in precipitation 2.9 NovDecember: 2.51 in precipitation 2.5 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: S Bend, IN (9 mi away); precipitation: Elkhart 4.8 Sw, IN (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6a.

Indiana planting zones →

Questions about 46561

What planting zone is ZIP code 46561?

ZIP code 46561 (Osceola, 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 Osceola, IN?

The median last spring frost (32 °F) near 46561 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 Osceola, IN?

The median first fall frost near 46561 is October 23, giving a median frost-free growing season of 181 days.

When should I plant tomatoes in 46561?

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 46561 get?

About 39.1 inches of precipitation a year (NOAA 1991–2020 normals, Elkhart 4.8 Sw station).

How hot do summers get in Osceola, 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 46561 have?

The USDA soil survey maps Tyner at the center of ZIP 46561: loamy sand, excessively drained, pH about 5.9 (moderately acidic).

Did spring come early in Osceola, IN in 2026?

Spring leaf-out near 46561 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 Osceola, IN?

Long-day onions: the longest day near 46561 is 15 h 12 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).