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

Planting zone for 47434 — Harrodsburg, IN

ZIP code 47434 (Harrodsburg, Monroe County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is April 20 and the first fall frost October 20.

Where ZIP 47434 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 20
First frostOct 20
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 Harrodsburg, 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 Harrodsburg, IN

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 20median — 50% chance of a later frost
Safe for tender plantsMay 7only 10% chance of frost after
First fall frostOctober 20median — 10% chance by Oct 6
Growing season181 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 7 and returns around October 30.

From the NOAA station Oolitic Purdue Ex Fm, IN — 9 miles away, elevation 653 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 47434

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 9 – Mar 23
SpinachSow outdoors · Mar 9 – Mar 30
Broccoli, cabbageStart indoors · Feb 9 – Feb 23
Broccoli, cabbageTransplant · Mar 30 – Apr 13
Onion setsPlant outdoors · Mar 23 – Apr 6
PotatoesPlant outdoors · Mar 30 – Apr 13
LettuceSow outdoors · Mar 23 – Apr 6
Carrots, beetsSow outdoors · Mar 30 – Apr 13
TomatoesStart indoors · Feb 23 – Mar 9
TomatoesTransplant · Apr 27 – May 11
Peppers, eggplantStart indoors · Feb 9 – Feb 23
Peppers, eggplantTransplant · May 4 – May 18
BeansSow outdoors · Apr 27 – May 11
Sweet cornSow outdoors · Apr 27 – May 11
Cucumbers, squashSow outdoors · Apr 27 – May 11
Fall lettuce, spinachSow outdoors · Aug 25 – Sep 8
GarlicPlant cloves · Oct 6 – Nov 10
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 20) and first fall frost (Oct 20) 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 47434 came on Mar 8 — 13 days earlier than the 1991–2020 average (Mar 21).

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 6b in Indiana

564 plants native to the lower 48 states, recorded in Indiana, and rated by the USDA to survive −5 °F or colder — the bottom of zone 6b. Each links to its USDA PLANTS profile.

Trees 72

Shrubs 105

Wildflowers & perennials 202

Grasses 162

Vines 11

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 Harrodsburg, IN.

Soil in Harrodsburg, IN

The soil mapped at the center of ZIP 47434 is Caneyville — silt loam, well drained.

TextureSilt loama good balance for most vegetables
pH5.3strongly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter3%moderate
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Caneyville silt loam, 12 to 18 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 47434; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Harrodsburg, IN

Summer high85 °Faverage high, July
Winter low21 °Faverage low, January
Hot days18days a year at 90 °F or more
Freezing nights119nights a year at 32 °F or less
Growing degree days3,484base 50 °F — the season’s usable heat
Longest day14 h 55 mindaylight on June 21
Shortest day9 h 25 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation47.1 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 38 °F, low 21 °F 38°21° JanFebruary: average high 43 °F, low 23 °F 43°23° FebMarch: average high 53 °F, low 31 °F 53°31° MarApril: average high 65 °F, low 41 °F 65°41° AprMay: average high 74 °F, low 52 °F 74°52° MayJune: average high 82 °F, low 61 °F 82°61° JunJuly: average high 85 °F, low 64 °F 85°64° JulAugust: average high 85 °F, low 62 °F 85°62° AugSeptember: average high 79 °F, low 55 °F 79°55° SepOctober: average high 67 °F, low 43 °F 67°43° OctNovember: average high 54 °F, low 33 °F 54°33° NovDecember: average high 42 °F, low 25 °F 42°25° Dec

Precipitation by month inches

0″1″2″3″4″5″6″January: 3.77 in precipitation 3.8 JanFebruary: 2.63 in precipitation 2.6 FebMarch: 3.51 in precipitation 3.5 MarApril: 5.09 in precipitation 5.1 AprMay: 5.31 in precipitation 5.3 MayJune: 5.28 in precipitation 5.3 JunJuly: 4.42 in precipitation 4.4 JulAugust: 3.71 in precipitation 3.7 AugSeptember: 2.77 in precipitation 2.8 SepOctober: 3.64 in precipitation 3.6 OctNovember: 3.52 in precipitation 3.5 NovDecember: 3.46 in precipitation 3.5 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Oolitic Purdue Ex Fm, IN (9 mi away); precipitation: Bedford 8.6 Nnw, IN (3 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6b.

Indiana planting zones →

Questions about 47434

What planting zone is ZIP code 47434?

ZIP code 47434 (Harrodsburg, 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 Harrodsburg, IN?

The median last spring frost (32 °F) near 47434 is April 20; after May 7 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Oolitic Purdue Ex Fm station.

When is the first frost in Harrodsburg, IN?

The median first fall frost near 47434 is October 20, giving a median frost-free growing season of 181 days.

When should I plant tomatoes in 47434?

Start tomato seeds indoors around Feb 23 – Mar 9 and set transplants outside around Apr 27 – May 11, one to three weeks after the median last frost.

How much rain and snow does 47434 get?

About 47.1 inches of precipitation a year (NOAA 1991–2020 normals, Bedford 8.6 Nnw station).

How hot do summers get in Harrodsburg, IN?

The average high peaks at 85 °F in July, with about 18 days a year at 90 °F or more.

What kind of soil does 47434 have?

The USDA soil survey maps Caneyville at the center of ZIP 47434: silt loam, well drained, pH about 5.3 (strongly acidic).

Did spring come early in Harrodsburg, IN in 2026?

Spring leaf-out near 47434 came on Mar 8 in 2026, 13 days earlier than the 1991–2020 average (Mar 21), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Harrodsburg, IN?

Intermediate onions: the longest day near 47434 is 14 h 55 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 47434 change?

Yes. The 2012 USDA map put 47434 in zone 6a; the 2023 map puts it in zone 6b. The newer map uses 1991–2020 data and more weather stations.