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

Planting zone for 40010 — Buckner, KY

ZIP code 40010 (Buckner, Oldham County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is April 12 and the first fall frost October 25.

Where ZIP 40010 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 12

First frostOct 25

2012 zone6b

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 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Buckner, 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 Buckner, KY

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostApril 12median — 50% chance of a later frost

Safe for tender plantsMay 1only 10% chance of frost after

First fall frostOctober 25median — 10% chance by Oct 11

Growing season193 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 31 and returns around November 3.

From the NOAA station Crestwood 4ne, KY — 2 miles away, elevation 781 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 40010

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 1 – Mar 15

SpinachSow outdoors · Mar 1 – Mar 22

Broccoli, cabbageStart indoors · Feb 1 – Feb 15

Broccoli, cabbageTransplant · Mar 22 – Apr 5

Onion setsPlant outdoors · Mar 15 – Mar 29

PotatoesPlant outdoors · Mar 22 – Apr 5

LettuceSow outdoors · Mar 15 – Mar 29

Carrots, beetsSow outdoors · Mar 22 – Apr 5

TomatoesStart indoors · Feb 15 – Mar 1

TomatoesTransplant · Apr 19 – May 3

Peppers, eggplantStart indoors · Feb 1 – Feb 15

Peppers, eggplantTransplant · Apr 26 – May 10

BeansSow outdoors · Apr 19 – May 3

Sweet cornSow outdoors · Apr 19 – May 3

Cucumbers, squashSow outdoors · Apr 19 – May 3

Fall lettuce, spinachSow outdoors · Aug 30 – Sep 13

GarlicPlant cloves · Oct 11 – Nov 15

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 12) and first fall frost (Oct 25) 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 40010 came on Mar 6 — 8 days earlier than the 1991–2020 average (Mar 14).

average
Mar 142026
Mar 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 6b in Kentucky

531 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 6b. 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 Buckner, KY.

Soil in Buckner, KY

The soil mapped at the center of ZIP 40010 is Beasley — silty clay loam, well drained.

TextureSilty clay loamholds water and nutrients; slow to drain and warm up

pH5.5moderately acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter1.25%low — add compost

Hydrologic groupCwater soaks in slowly

Farmland classNot prime farmlandUSDA classification

Map unit: Beasley silty clay loam, 6 to 12 percent slopes, severely eroded.

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 40010; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Buckner, KY

Summer high88 °Faverage high, July

Winter low23 °Faverage low, January

Hot days37days a year at 90 °F or more

Freezing nights105nights a year at 32 °F or less

Growing degree days3,944base 50 °F — the season’s usable heat

Longest day14 h 51 mindaylight on June 21

Shortest day9 h 29 mindaylight on December 21

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

Precipitation52.8 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: Crestwood 4ne, KY (2 mi away); precipitation: Park Lake 1.8 Ne, KY (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

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

Pewee Valley, KY · 5 mi

Louisville, KY · 7 mi

402417a

Louisville, KY · 8 mi

Kentucky planting zones →

Questions about 40010

What planting zone is ZIP code 40010?

ZIP code 40010 (Buckner, KY) 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 Buckner, KY?

The median last spring frost (32 °F) near 40010 is April 12; after May 1 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Crestwood 4ne station.

When is the first frost in Buckner, KY?

The median first fall frost near 40010 is October 25, giving a median frost-free growing season of 193 days.

When should I plant tomatoes in 40010?

Start tomato seeds indoors around Feb 15 – Mar 1 and set transplants outside around Apr 19 – May 3, one to three weeks after the median last frost.

How much rain and snow does 40010 get?

About 52.8 inches of precipitation a year (NOAA 1991–2020 normals, Park Lake 1.8 Ne station).

How hot do summers get in Buckner, KY?

The average high peaks at 88 °F in July, with about 37 days a year at 90 °F or more.

What kind of soil does 40010 have?

The USDA soil survey maps Beasley at the center of ZIP 40010: silty clay loam, well drained, pH about 5.5 (moderately acidic).

Did spring come early in Buckner, KY in 2026?

Spring leaf-out near 40010 came on Mar 6 in 2026, 8 days earlier than the 1991–2020 average (Mar 14), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Buckner, KY?

Intermediate onions: the longest day near 40010 is 14 h 51 min, so day-neutral types bulb best; long-day varieties may not bulb fully.