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

Planting zone for 40820 — Cranks, KY

ZIP code 40820 (Cranks, Harlan County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is April 22 and the first fall frost October 20.

Where ZIP 40820 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 22

First frostOct 20

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 Cranks, 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 Cranks, KY

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostApril 22median — 50% chance of a later frost

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

First fall frostOctober 20median — 10% chance by Oct 8

Growing season179 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 10 and returns around October 29.

From the NOAA station Pennington Gap, VA — 9 miles away, elevation 1,362 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 40820

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 11 – Mar 25

SpinachSow outdoors · Mar 11 – Apr 1

Broccoli, cabbageStart indoors · Feb 11 – Feb 25

Broccoli, cabbageTransplant · Apr 1 – Apr 15

Onion setsPlant outdoors · Mar 25 – Apr 8

PotatoesPlant outdoors · Apr 1 – Apr 15

LettuceSow outdoors · Mar 25 – Apr 8

Carrots, beetsSow outdoors · Apr 1 – Apr 15

TomatoesStart indoors · Feb 25 – Mar 11

TomatoesTransplant · Apr 29 – May 13

Peppers, eggplantStart indoors · Feb 11 – Feb 25

Peppers, eggplantTransplant · May 6 – May 20

BeansSow outdoors · Apr 29 – May 13

Sweet cornSow outdoors · Apr 29 – May 13

Cucumbers, squashSow outdoors · Apr 29 – May 13

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 22) 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 40820 came on Mar 2 — 9 days earlier than the 1991–2020 average (Mar 11).

average
Mar 112026
Mar 2

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 Cranks, KY.

Soil in Cranks, KY

The soil mapped at the center of ZIP 40820 is Highsplint — very channery silt loam, well drained.

TextureVery channery silt loama good balance for most vegetables

pH5.1strongly acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter2.75%moderate

Hydrologic groupAwater soaks in fast

Farmland classNot prime farmlandUSDA classification

Map unit: Highsplint-Cloverlick-Guyandotte complex, 35 to 75 percent slopes, very 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 40820; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Cranks, KY

Summer high85 °Faverage high, July

Winter low23 °Faverage low, January

Hot days15days a year at 90 °F or more

Freezing nights120nights a year at 32 °F or less

Growing degree days3,566base 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

Precipitation49.7 inper year, rain and melted snow

Snowfall9 inper year; 6 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: Pennington Gap, VA (9 mi away); precipitation: Pennington Gap, VA (9 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 7a.

Saint Charles, VA · 6 mi

408017a

Ages Brookside, KY · 7 mi

408497a

Lejunior, KY · 7 mi

408297a

Grays Knob, KY · 8 mi

Kentucky planting zones →

Questions about 40820

What planting zone is ZIP code 40820?

ZIP code 40820 (Cranks, 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 Cranks, KY?

The median last spring frost (32 °F) near 40820 is April 22; after May 10 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Pennington Gap station.

When is the first frost in Cranks, KY?

The median first fall frost near 40820 is October 20, giving a median frost-free growing season of 179 days.

When should I plant tomatoes in 40820?

Start tomato seeds indoors around Feb 25 – Mar 11 and set transplants outside around Apr 29 – May 13, one to three weeks after the median last frost.

How much rain and snow does 40820 get?

About 49.7 inches of precipitation a year and 9 inches of snowfall (NOAA 1991–2020 normals, Pennington Gap station).

How hot do summers get in Cranks, KY?

The average high peaks at 85 °F in July, with about 15 days a year at 90 °F or more.

What kind of soil does 40820 have?

The USDA soil survey maps Highsplint at the center of ZIP 40820: very channery silt loam, well drained, pH about 5.1 (strongly acidic).

Did spring come early in Cranks, KY in 2026?

Spring leaf-out near 40820 came on Mar 2 in 2026, 9 days earlier than the 1991–2020 average (Mar 11), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Cranks, KY?

Intermediate onions: the longest day near 40820 is 14 h 41 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 40820 change?

Yes. The 2012 USDA map put 40820 in zone 6b; the 2023 map puts it in zone 7a. The newer map uses 1991–2020 data and more weather stations.