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

Planting zone for 47437 — Huron, IN

ZIP code 47437 (Huron, Lawrence County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is April 15 and the first fall frost October 23.

Where ZIP 47437 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.

Zone6b−5 to 0 °F
Coldest night−20.6 to −17.8 °C
Last frostApr 15
First frostOct 23
2012 zone6a

Was 6a 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 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Huron, 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 Huron, IN

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 15median — 50% chance of a later frost
Safe for tender plantsMay 2only 10% chance of frost after
First fall frostOctober 23median — 10% chance by Oct 10
Growing season189 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 2 and returns around November 2.

From the NOAA station Shoals 8 S, IN — 13 miles away, elevation 476 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 47437

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 4 – Mar 18
SpinachSow outdoors · Mar 4 – Mar 25
Broccoli, cabbageStart indoors · Feb 4 – Feb 18
Broccoli, cabbageTransplant · Mar 25 – Apr 8
Onion setsPlant outdoors · Mar 18 – Apr 1
PotatoesPlant outdoors · Mar 25 – Apr 8
LettuceSow outdoors · Mar 18 – Apr 1
Carrots, beetsSow outdoors · Mar 25 – Apr 8
TomatoesStart indoors · Feb 18 – Mar 4
TomatoesTransplant · Apr 22 – May 6
Peppers, eggplantStart indoors · Feb 4 – Feb 18
Peppers, eggplantTransplant · Apr 29 – May 13
BeansSow outdoors · Apr 22 – May 6
Sweet cornSow outdoors · Apr 22 – May 6
Cucumbers, squashSow outdoors · Apr 22 – May 6
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 15) 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 47437 came on Mar 7 — 11 days earlier than the 1991–2020 average (Mar 18).

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).

Soil in Huron, IN

The soil mapped at the center of ZIP 47437 is Adyeville — silt loam, somewhat excessively drained.

TextureSilt loama good balance for most vegetables
pH5.4strongly acidic; most vegetables like 6.0–7.0
DrainageSomewhat excessively drainednatural drainage class
Organic matter3.8%moderate
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Adyeville-Tipsaw-Wellston complex, 18 to 50 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 47437; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Huron, IN

Summer high88 °Faverage high, July
Winter low23 °Faverage low, January
Hot days28days a year at 90 °F or more
Freezing nights116nights a year at 32 °F or less
Growing degree days4,047base 50 °F — the season’s usable heat
Longest day14 h 53 mindaylight on June 21
Shortest day9 h 27 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation50.5 inper year, rain and melted snow
Snowfall13 inper year

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 41 °F, low 23 °F 41°23° JanFebruary: average high 46 °F, low 25 °F 46°25° FebMarch: average high 56 °F, low 33 °F 56°33° MarApril: average high 68 °F, low 43 °F 68°43° AprMay: average high 77 °F, low 53 °F 77°53° MayJune: average high 85 °F, low 63 °F 85°63° JunJuly: average high 88 °F, low 66 °F 88°66° JulAugust: average high 88 °F, low 64 °F 88°64° AugSeptember: average high 82 °F, low 56 °F 82°56° SepOctober: average high 70 °F, low 44 °F 70°44° OctNovember: average high 56 °F, low 35 °F 56°35° NovDecember: average high 45 °F, low 28 °F 45°28° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″6″January: 3.59 in precipitation, 4.2 in snowfall 3.6❄4 JanFebruary: 3.09 in precipitation, 4.1 in snowfall 3.1❄4 FebMarch: 4.44 in precipitation, 1.3 in snowfall 4.4❄1 MarApril: 5.33 in precipitation, 0.1 in snowfall 5.3 AprMay: 5.93 in precipitation 5.9 MayJune: 4.99 in precipitation 5.0 JunJuly: 4.59 in precipitation 4.6 JulAugust: 3.33 in precipitation 3.3 AugSeptember: 3.49 in precipitation 3.5 SepOctober: 3.50 in precipitation, 0.1 in snowfall 3.5 OctNovember: 4.09 in precipitation, 0.3 in snowfall 4.1 NovDecember: 4.17 in precipitation, 3.1 in snowfall 4.2❄3 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Shoals 8 S, IN (13 mi away); precipitation: Williams 3 Sw, IN (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6b.

475816b
Shoals, IN · 6 mi
474696b
West Baden Springs, IN · 7 mi
474706b
Williams, IN · 7 mi
474466b
Mitchell, IN · 9 mi
475226b
Crane, IN · 13 mi
475536b
Loogootee, IN · 13 mi
474516b
Oolitic, IN · 15 mi
474526b
Orleans, IN · 15 mi

Indiana planting zones →

Questions about 47437

What planting zone is ZIP code 47437?

ZIP code 47437 (Huron, IN) is in USDA hardiness zone 6b on the 2023 map: the coldest night of an average winter reaches −5 to 0 °F (−20.6 to −17.8 °C).

When is the last frost in Huron, IN?

The median last spring frost (32 °F) near 47437 is April 15; after May 2 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Shoals 8 S station.

When is the first frost in Huron, IN?

The median first fall frost near 47437 is October 23, giving a median frost-free growing season of 189 days.

When should I plant tomatoes in 47437?

Start tomato seeds indoors around Feb 18 – Mar 4 and set transplants outside around Apr 22 – May 6, one to three weeks after the median last frost.

How much rain and snow does 47437 get?

About 50.5 inches of precipitation a year and 13 inches of snowfall (NOAA 1991–2020 normals, Williams 3 Sw station).

How hot do summers get in Huron, IN?

The average high peaks at 88 °F in July, with about 28 days a year at 90 °F or more.

What kind of soil does 47437 have?

The USDA soil survey maps Adyeville at the center of ZIP 47437: silt loam, somewhat excessively drained, pH about 5.4 (strongly acidic).

Did spring come early in Huron, IN in 2026?

Spring leaf-out near 47437 came on Mar 7 in 2026, 11 days earlier than the 1991–2020 average (Mar 18), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Huron, IN?

Intermediate onions: the longest day near 47437 is 14 h 53 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 47437 change?

Yes. The 2012 USDA map put 47437 in zone 6a; the 2023 map puts it in zone 6b. The newer map uses 1991–2020 data and more weather stations.