Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 42048 — Hardin, KY

ZIP code 42048 (Hardin, Marshall County) is in USDA zone 7b: the coldest winter night averages 5 to 10 °F. The median last spring frost is April 9 and the first fall frost October 19.

Where ZIP 42048 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.

Zone7b5 to 10 °F

Coldest night−15 to −12.2 °C

Last frostApr 9

First frostOct 19

2012 zone7a

Was 7a 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 7b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Hardin, KY…

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 Hardin, KY

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostApril 9median — 50% chance of a later frost

Safe for tender plantsApril 28only 10% chance of frost after

First fall frostOctober 19median — 10% chance by Oct 6

Growing season192 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 31 and returns around October 28.

From the NOAA station Benton, KY — 7 miles away, elevation 364 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 42048

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Feb 26 – Mar 12

SpinachSow outdoors · Feb 26 – Mar 19

Broccoli, cabbageStart indoors · Jan 29 – Feb 12

Broccoli, cabbageTransplant · Mar 19 – Apr 2

Onion setsPlant outdoors · Mar 12 – Mar 26

PotatoesPlant outdoors · Mar 19 – Apr 2

LettuceSow outdoors · Mar 12 – Mar 26

Carrots, beetsSow outdoors · Mar 19 – Apr 2

TomatoesStart indoors · Feb 12 – Feb 26

TomatoesTransplant · Apr 16 – Apr 30

Peppers, eggplantStart indoors · Jan 29 – Feb 12

Peppers, eggplantTransplant · Apr 23 – May 7

BeansSow outdoors · Apr 16 – Apr 30

Sweet cornSow outdoors · Apr 16 – Apr 30

Cucumbers, squashSow outdoors · Apr 16 – Apr 30

Fall lettuce, spinachSow outdoors · Aug 24 – Sep 7

GarlicPlant cloves · Oct 5 – Nov 9

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 9) and first fall frost (Oct 19) 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 42048 came on Feb 25 — 5 days earlier than the 1991–2020 average (Mar 2).

average
Mar 22026
Feb 25

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 7b in Kentucky

552 plants native to the lower 48 states, recorded in Kentucky, and rated by the USDA to survive 5 °F or colder — the bottom of zone 7b. Each links to its USDA PLANTS profile.

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 Hardin, KY.

Soil in Hardin, KY

The soil mapped at the center of ZIP 42048 is Kurk — silt loam, somewhat poorly drained.

TextureSilt loama good balance for most vegetables

pH5.8moderately acidic; most vegetables like 6.0–7.0

DrainageSomewhat poorly drainedconsider raised beds

Organic matter2%moderate

Hydrologic groupC/Dslow when drained; wet otherwise

Farmland classPrime farmland if drainedUSDA classification

Map unit: Kurk silt loam, 0 to 3 percent slopes, rarely flooded.

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 42048; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Hardin, KY

Summer high90 °Faverage high, July

Winter low23 °Faverage low, January

Hot days54days a year at 90 °F or more

Freezing nights103nights a year at 32 °F or less

Growing degree days4,147base 50 °F — the season’s usable heat

Longest day14 h 41 mindaylight on June 21

Shortest day9 h 38 mindaylight on December 21

Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully

Precipitation55.8 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Benton, KY (7 mi away); precipitation: Kenlake Resort, KY (9 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

3 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

Gilbertsville, KY · 14 mi

420407b

Farmington, KY · 15 mi

420827a

Symsonia, KY · 16 mi

Kentucky planting zones →

Questions about 42048

What planting zone is ZIP code 42048?

ZIP code 42048 (Hardin, KY) is in USDA hardiness zone 7b on the 2023 map: the coldest night of an average winter reaches 5 to 10 °F (−15 to −12.2 °C).

When is the last frost in Hardin, KY?

The median last spring frost (32 °F) near 42048 is April 9; after April 28 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Benton station.

When is the first frost in Hardin, KY?

The median first fall frost near 42048 is October 19, giving a median frost-free growing season of 192 days.

When should I plant tomatoes in 42048?

Start tomato seeds indoors around Feb 12 – Feb 26 and set transplants outside around Apr 16 – Apr 30, one to three weeks after the median last frost.

How much rain and snow does 42048 get?

About 55.8 inches of precipitation a year (NOAA 1991–2020 normals, Kenlake Resort station).

How hot do summers get in Hardin, KY?

The average high peaks at 90 °F in July, with about 54 days a year at 90 °F or more.

What kind of soil does 42048 have?

The USDA soil survey maps Kurk at the center of ZIP 42048: silt loam, somewhat poorly drained, pH about 5.8 (moderately acidic).

Did spring come early in Hardin, KY in 2026?

Spring leaf-out near 42048 came on Feb 25 in 2026, 5 days earlier than the 1991–2020 average (Mar 2), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Hardin, KY?

Intermediate onions: the longest day near 42048 is 14 h 41 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 42048 change?

Yes. The 2012 USDA map put 42048 in zone 7a; the 2023 map puts it in zone 7b. The newer map uses 1991–2020 data and more weather stations.