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

Planting zone for 18621 — Hunlock Creek, PA

ZIP code 18621 (Hunlock Creek, Luzerne County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is May 4 and the first fall frost October 11.

Where ZIP 18621 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.

Zone6a−10 to −5 °F
Coldest night−23.3 to −20.6 °C
Last frostMay 4
First frostOct 11
2012 zone6a

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 6a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Hunlock Creek, PA…

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 Hunlock Creek, PA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 4median — 50% chance of a later frost
Safe for tender plantsMay 19only 10% chance of frost after
First fall frostOctober 11median — 10% chance by Sep 29
Growing season159 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 22 and returns around October 24.

From the NOAA station Benton 3 Ne, PA — 13 miles away, elevation 1,096 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 18621

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 23 – Apr 6
SpinachSow outdoors · Mar 23 – Apr 13
Broccoli, cabbageStart indoors · Feb 23 – Mar 9
Broccoli, cabbageTransplant · Apr 13 – Apr 27
Onion setsPlant outdoors · Apr 6 – Apr 20
PotatoesPlant outdoors · Apr 13 – Apr 27
LettuceSow outdoors · Apr 6 – Apr 20
Carrots, beetsSow outdoors · Apr 13 – Apr 27
TomatoesStart indoors · Mar 9 – Mar 23
TomatoesTransplant · May 11 – May 25
Peppers, eggplantStart indoors · Feb 23 – Mar 9
Peppers, eggplantTransplant · May 18 – Jun 1
BeansSow outdoors · May 11 – May 25
Sweet cornSow outdoors · May 11 – May 25
Cucumbers, squashSow outdoors · May 11 – May 25
Fall lettuce, spinachSow outdoors · Aug 16 – Aug 30
GarlicPlant cloves · Sep 27 – Nov 1
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 4) and first fall frost (Oct 11) 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 18621 came on Apr 1 — 7 days earlier than the 1991–2020 average (Apr 8).

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 6a in Pennsylvania

598 plants native to the lower 48 states, recorded in Pennsylvania, and rated by the USDA to survive −10 °F or colder — the bottom of zone 6a. Each links to its USDA PLANTS profile.

Trees 76

Shrubs 121

Wildflowers & perennials 207

Grasses 170

Vines 9

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 Hunlock Creek, PA.

Soil in Hunlock Creek, PA

The soil mapped at the center of ZIP 18621 is Oquaga — moderately decomposed plant material, well drained.

TextureModerately decomposed plant materialtop layer
pH4.8strongly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter80%high
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Oquaga and Lordstown channery silt loams, 8 to 25 percent slopes, rubbly.

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 18621; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Hunlock Creek, PA

Summer high80 °Faverage high, July
Winter low16 °Faverage low, January
Hot days4days a year at 90 °F or more
Freezing nights145nights a year at 32 °F or less
Growing degree days2,377base 50 °F — the season’s usable heat
Longest day15 h 09 mindaylight on June 21
Shortest day9 h 12 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation47.5 inper year, rain and melted snow
Snowfall36 inper year; 52 days with snow on the ground

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 33 °F, low 16 °F 33°16° JanFebruary: average high 36 °F, low 18 °F 36°18° FebMarch: average high 44 °F, low 25 °F 44°25° MarApril: average high 58 °F, low 35 °F 58°35° AprMay: average high 69 °F, low 46 °F 69°46° MayJune: average high 76 °F, low 55 °F 76°55° JunJuly: average high 80 °F, low 58 °F 80°58° JulAugust: average high 78 °F, low 57 °F 78°57° AugSeptember: average high 72 °F, low 50 °F 72°50° SepOctober: average high 60 °F, low 39 °F 60°39° OctNovember: average high 48 °F, low 31 °F 48°31° NovDecember: average high 38 °F, low 22 °F 38°22° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 3.40 in precipitation, 10.7 in snowfall 3.4❄11 JanFebruary: 2.57 in precipitation, 10.2 in snowfall 2.6❄10 FebMarch: 3.44 in precipitation, 6 in snowfall 3.4❄6 MarApril: 4.20 in precipitation, 0.8 in snowfall 4.2❄1 AprMay: 4.34 in precipitation 4.3 MayJune: 4.70 in precipitation 4.7 JunJuly: 4.52 in precipitation 4.5 JulAugust: 4.43 in precipitation 4.4 AugSeptember: 4.58 in precipitation 4.6 SepOctober: 4.35 in precipitation, 0.2 in snowfall 4.3 OctNovember: 3.18 in precipitation, 1.1 in snowfall 3.2❄1 NovDecember: 3.75 in precipitation, 6.6 in snowfall 3.8❄7 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Benton 3 Ne, PA (13 mi away); precipitation: Shickshinny 3 N, PA (6 mi away). 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.

Pennsylvania planting zones →

Questions about 18621

What planting zone is ZIP code 18621?

ZIP code 18621 (Hunlock Creek, PA) is in USDA hardiness zone 6a on the 2023 map: the coldest night of an average winter reaches −10 to −5 °F (−23.3 to −20.6 °C).

When is the last frost in Hunlock Creek, PA?

The median last spring frost (32 °F) near 18621 is May 4; after May 19 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Benton 3 Ne station.

When is the first frost in Hunlock Creek, PA?

The median first fall frost near 18621 is October 11, giving a median frost-free growing season of 159 days.

When should I plant tomatoes in 18621?

Start tomato seeds indoors around Mar 9 – Mar 23 and set transplants outside around May 11 – May 25, one to three weeks after the median last frost.

How much rain and snow does 18621 get?

About 47.5 inches of precipitation a year and 36 inches of snowfall (NOAA 1991–2020 normals, Shickshinny 3 N station).

How hot do summers get in Hunlock Creek, PA?

The average high peaks at 80 °F in July, with about 4 days a year at 90 °F or more.

What kind of soil does 18621 have?

The USDA soil survey maps Oquaga at the center of ZIP 18621: moderately decomposed plant material, well drained, pH about 4.8 (strongly acidic).

Did spring come early in Hunlock Creek, PA in 2026?

Spring leaf-out near 18621 came on Apr 1 in 2026, 7 days earlier than the 1991–2020 average (Apr 8), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Hunlock Creek, PA?

Long-day onions: the longest day near 18621 is 15 h 09 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).