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 zoomNot 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.
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 ServiceLoading 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
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
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).
Apr 62026
Mar 23
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.
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
Average high and low, by month
Precipitation by month inches
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.
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).