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

Planting zone for 42518 — Bronston, KY

ZIP code 42518 (Bronston, Pulaski County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is April 18 and the first fall frost October 26.

Where ZIP 42518 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.

Zone7a0 to 5 °F

Coldest night−17.8 to −15 °C

Last frostApr 18

First frostOct 26

2012 zone6b

Was 6b 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 7a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Bronston, 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 Bronston, KY

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostApril 18median — 50% chance of a later frost

Safe for tender plantsMay 5only 10% chance of frost after

First fall frostOctober 26median — 10% chance by Oct 14

Growing season190 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 4 and returns around November 3.

From the NOAA station Monticello 3 Ne, KY — 11 miles away, elevation 978 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 42518

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 7 – Mar 21

SpinachSow outdoors · Mar 7 – Mar 28

Broccoli, cabbageStart indoors · Feb 7 – Feb 21

Broccoli, cabbageTransplant · Mar 28 – Apr 11

Onion setsPlant outdoors · Mar 21 – Apr 4

PotatoesPlant outdoors · Mar 28 – Apr 11

LettuceSow outdoors · Mar 21 – Apr 4

Carrots, beetsSow outdoors · Mar 28 – Apr 11

TomatoesStart indoors · Feb 21 – Mar 7

TomatoesTransplant · Apr 25 – May 9

Peppers, eggplantStart indoors · Feb 7 – Feb 21

Peppers, eggplantTransplant · May 2 – May 16

BeansSow outdoors · Apr 25 – May 9

Sweet cornSow outdoors · Apr 25 – May 9

Cucumbers, squashSow outdoors · Apr 25 – May 9

Fall lettuce, spinachSow outdoors · Aug 31 – Sep 14

GarlicPlant cloves · Oct 12 – Nov 16

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 18) and first fall frost (Oct 26) 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 42518 came on Mar 1 — 3 days earlier than the 1991–2020 average (Mar 4).

average
Mar 42026
Mar 1

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 7a in Kentucky

547 plants native to the lower 48 states, recorded in Kentucky, and rated by the USDA to survive 0 °F or colder — the bottom of zone 7a. 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 Bronston, KY.

Soil in Bronston, KY

The soil mapped at the center of ZIP 42518 is Beetree — channery silt loam, well drained.

TextureChannery silt loama good balance for most vegetables

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

DrainageWell drainednatural drainage class

Organic matter3.5%moderate

Hydrologic groupBwater soaks in moderately

Farmland classNot prime farmlandUSDA classification

Map unit: Beetree-Muse-Zenith complex, 15 to 40 percent slopes, stony.

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 42518; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Bronston, KY

Summer high86 °Faverage high, July

Winter low26 °Faverage low, January

Hot days24days a year at 90 °F or more

Freezing nights99nights a year at 32 °F or less

Growing degree days4,014base 50 °F — the season’s usable heat

Longest day14 h 42 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

Precipitation52.5 inper year, rain and melted snow

Snowfall14 inper year; 8 days with snow on the ground

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Monticello 3 Ne, KY (11 mi away); precipitation: Monticello 3 Ne, KY (11 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 7a.

Parkers Lake, KY · 12 mi

426337a

Monticello, KY · 13 mi

Whitley City, KY · 13 mi

Kentucky planting zones →

Questions about 42518

What planting zone is ZIP code 42518?

ZIP code 42518 (Bronston, KY) is in USDA hardiness zone 7a on the 2023 map: the coldest night of an average winter reaches 0 to 5 °F (−17.8 to −15 °C).

When is the last frost in Bronston, KY?

The median last spring frost (32 °F) near 42518 is April 18; after May 5 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Monticello 3 Ne station.

When is the first frost in Bronston, KY?

The median first fall frost near 42518 is October 26, giving a median frost-free growing season of 190 days.

When should I plant tomatoes in 42518?

Start tomato seeds indoors around Feb 21 – Mar 7 and set transplants outside around Apr 25 – May 9, one to three weeks after the median last frost.

How much rain and snow does 42518 get?

About 52.5 inches of precipitation a year and 14 inches of snowfall (NOAA 1991–2020 normals, Monticello 3 Ne station).

How hot do summers get in Bronston, KY?

The average high peaks at 86 °F in July, with about 24 days a year at 90 °F or more.

What kind of soil does 42518 have?

The USDA soil survey maps Beetree at the center of ZIP 42518: channery silt loam, well drained, pH about 5.5 (moderately acidic).

Did spring come early in Bronston, KY in 2026?

Spring leaf-out near 42518 came on Mar 1 in 2026, 3 days earlier than the 1991–2020 average (Mar 4), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Bronston, KY?

Intermediate onions: the longest day near 42518 is 14 h 42 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 42518 change?

Yes. The 2012 USDA map put 42518 in zone 6b; the 2023 map puts it in zone 7a. The newer map uses 1991–2020 data and more weather stations.