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

Planting zone for 16725 — Custer City, PA

ZIP code 16725 (Custer City, McKean County) is in USDA zone 5b: the coldest winter night averages −15 to −10 °F. The median last spring frost is May 18 and the first fall frost October 4.

Where ZIP 16725 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.

Zone5b−15 to −10 °F

Coldest night−26.1 to −23.3 °C

Last frostMay 18

First frostOct 4

2012 zone5a

Was 5a 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 5b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Custer City, 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 Custer City, PA

JanFebMarAprMayJunJulAugSepOctNovDec

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

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

Safe for tender plantsMay 31only 10% chance of frost after

First fall frostOctober 4median — 10% chance by Sep 21

Growing season140 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 4 and returns around October 17.

From the NOAA station Bradford 4sw Rsch 5, PA — 2 miles away, elevation 1,660 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 16725

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Apr 6 – Apr 20

SpinachSow outdoors · Apr 6 – Apr 27

Broccoli, cabbageStart indoors · Mar 9 – Mar 23

Broccoli, cabbageTransplant · Apr 27 – May 11

Onion setsPlant outdoors · Apr 20 – May 4

PotatoesPlant outdoors · Apr 27 – May 11

LettuceSow outdoors · Apr 20 – May 4

Carrots, beetsSow outdoors · Apr 27 – May 11

TomatoesStart indoors · Mar 23 – Apr 6

TomatoesTransplant · May 25 – Jun 8

Peppers, eggplantStart indoors · Mar 9 – Mar 23

Peppers, eggplantTransplant · Jun 1 – Jun 15

BeansSow outdoors · May 25 – Jun 8

Sweet cornSow outdoors · May 25 – Jun 8

Cucumbers, squashSow outdoors · May 25 – Jun 8

Fall lettuce, spinachSow outdoors · Aug 9 – Aug 23

GarlicPlant cloves · Sep 20 – Oct 25

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 18) and first fall frost (Oct 4) 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 16725 came on Apr 5 — 9 days earlier than the 1991–2020 average (Apr 14).

average
Apr 142026
Apr 5

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).

Soil in Custer City, PA

The soil mapped at the center of ZIP 16725 is Hazleton — channery loam, well drained.

TextureChannery loama good balance for most vegetables

pH4.6strongly acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter3%moderate

Hydrologic groupAwater soaks in fast

Farmland classNot prime farmlandUSDA classification

Map unit: Hazleton channery loam, 8 to 25 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 16725; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Custer City, PA

Summer high79 °Faverage high, July

Winter low13 °Faverage low, January

Hot days1days a year at 90 °F or more

Freezing nights169nights a year at 32 °F or less

Growing degree days2,058base 50 °F — the season’s usable heat

Longest day15 h 14 mindaylight on June 21

Shortest day9 h 07 mindaylight on December 21

Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)

Precipitation49.6 inper year, rain and melted snow

Snowfall75 inper year; 89 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: Bradford 4sw Rsch 5, PA (2 mi away); precipitation: Bradford 4sw Rsch 5, PA (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 5b.

Derrick City, PA · 9 mi

167455b

Rixford, PA · 9 mi

147535b

Limestone, NY · 10 mi

Pennsylvania planting zones →

Questions about 16725

What planting zone is ZIP code 16725?

ZIP code 16725 (Custer City, PA) is in USDA hardiness zone 5b on the 2023 map: the coldest night of an average winter reaches −15 to −10 °F (−26.1 to −23.3 °C).

When is the last frost in Custer City, PA?

The median last spring frost (32 °F) near 16725 is May 18; after May 31 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Bradford 4sw Rsch 5 station.

When is the first frost in Custer City, PA?

The median first fall frost near 16725 is October 4, giving a median frost-free growing season of 140 days.

When should I plant tomatoes in 16725?

Start tomato seeds indoors around Mar 23 – Apr 6 and set transplants outside around May 25 – Jun 8, one to three weeks after the median last frost.

How much rain and snow does 16725 get?

About 49.6 inches of precipitation a year and 75 inches of snowfall (NOAA 1991–2020 normals, Bradford 4sw Rsch 5 station).

How hot do summers get in Custer City, PA?

The average high peaks at 79 °F in July, with about 1 days a year at 90 °F or more.

What kind of soil does 16725 have?

The USDA soil survey maps Hazleton at the center of ZIP 16725: channery loam, well drained, pH about 4.6 (strongly acidic).

Did spring come early in Custer City, PA in 2026?

Spring leaf-out near 16725 came on Apr 5 in 2026, 9 days earlier than the 1991–2020 average (Apr 14), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Custer City, PA?

Long-day onions: the longest day near 16725 is 15 h 14 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 16725 change?

Yes. The 2012 USDA map put 16725 in zone 5a; the 2023 map puts it in zone 5b. The newer map uses 1991–2020 data and more weather stations.