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

Planting zone for 16002 — Butler, PA

ZIP code 16002 (Butler, Butler County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is May 7 and the first fall frost October 14.

Where ZIP 16002 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 7
First frostOct 14
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 Butler, 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 Butler, PA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 7median — 50% chance of a later frost
Safe for tender plantsMay 23only 10% chance of frost after
First fall frostOctober 14median — 10% chance by Oct 1
Growing season159 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 26 and returns around October 27.

From the NOAA station Butler 2 Sw, PA — 4 miles away, elevation 1,001 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 16002

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 26 – Apr 9
SpinachSow outdoors · Mar 26 – Apr 16
Broccoli, cabbageStart indoors · Feb 26 – Mar 12
Broccoli, cabbageTransplant · Apr 16 – Apr 30
Onion setsPlant outdoors · Apr 9 – Apr 23
PotatoesPlant outdoors · Apr 16 – Apr 30
LettuceSow outdoors · Apr 9 – Apr 23
Carrots, beetsSow outdoors · Apr 16 – Apr 30
TomatoesStart indoors · Mar 12 – Mar 26
TomatoesTransplant · May 14 – May 28
Peppers, eggplantStart indoors · Feb 26 – Mar 12
Peppers, eggplantTransplant · May 21 – Jun 4
BeansSow outdoors · May 14 – May 28
Sweet cornSow outdoors · May 14 – May 28
Cucumbers, squashSow outdoors · May 14 – May 28
Fall lettuce, spinachSow outdoors · Aug 19 – Sep 2
GarlicPlant cloves · Sep 30 – Nov 4
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 7) and first fall frost (Oct 14) 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 16002 came on Mar 16 — 18 days earlier than the 1991–2020 average (Apr 3).

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 Butler, PA.

Soil in Butler, PA

The soil mapped at the center of ZIP 16002 is Gilpin — silt loam, well drained.

TextureSilt loama good balance for most vegetables
pH4.6strongly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter2.25%moderate
Hydrologic groupCwater soaks in slowly
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Gilpin-Wharton silt loams, 8 to 15 percent slopes.

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 16002; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Butler, PA

Summer high82 °Faverage high, July
Winter low17 °Faverage low, January
Hot days7days a year at 90 °F or more
Freezing nights140nights a year at 32 °F or less
Growing degree days2,533base 50 °F — the season’s usable heat
Longest day15 h 06 mindaylight on June 21
Shortest day9 h 14 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation43.2 inper year, rain and melted snow
Snowfall35 inper year; 53 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 34 °F, low 17 °F 34°17° JanFebruary: average high 37 °F, low 18 °F 37°18° FebMarch: average high 46 °F, low 25 °F 46°25° MarApril: average high 60 °F, low 35 °F 60°35° AprMay: average high 70 °F, low 45 °F 70°45° MayJune: average high 78 °F, low 54 °F 78°54° JunJuly: average high 82 °F, low 58 °F 82°58° JulAugust: average high 81 °F, low 57 °F 81°57° AugSeptember: average high 74 °F, low 50 °F 74°50° SepOctober: average high 62 °F, low 39 °F 62°39° OctNovember: average high 50 °F, low 30 °F 50°30° NovDecember: average high 39 °F, low 23 °F 39°23° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 3.36 in precipitation, 11.3 in snowfall 3.4❄11 JanFebruary: 2.66 in precipitation, 9.7 in snowfall 2.7❄10 FebMarch: 3.28 in precipitation, 5.3 in snowfall 3.3❄5 MarApril: 3.50 in precipitation, 0.6 in snowfall 3.5❄1 AprMay: 3.80 in precipitation 3.8 MayJune: 4.33 in precipitation 4.3 JunJuly: 4.16 in precipitation 4.2 JulAugust: 4.02 in precipitation 4.0 AugSeptember: 4.09 in precipitation 4.1 SepOctober: 3.30 in precipitation, 0.1 in snowfall 3.3 OctNovember: 3.34 in precipitation, 1.1 in snowfall 3.3❄1 NovDecember: 3.37 in precipitation, 6.8 in snowfall 3.4❄7 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Butler 2 Sw, PA (4 mi away); precipitation: Butler 2 Sw, PA (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

All 3 ZIP codes in Butler → · Pennsylvania planting zones →

Questions about 16002

What planting zone is ZIP code 16002?

ZIP code 16002 (Butler, 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 Butler, PA?

The median last spring frost (32 °F) near 16002 is May 7; after May 23 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Butler 2 Sw station.

When is the first frost in Butler, PA?

The median first fall frost near 16002 is October 14, giving a median frost-free growing season of 159 days.

When should I plant tomatoes in 16002?

Start tomato seeds indoors around Mar 12 – Mar 26 and set transplants outside around May 14 – May 28, one to three weeks after the median last frost.

How much rain and snow does 16002 get?

About 43.2 inches of precipitation a year and 35 inches of snowfall (NOAA 1991–2020 normals, Butler 2 Sw station).

How hot do summers get in Butler, PA?

The average high peaks at 82 °F in July, with about 7 days a year at 90 °F or more.

What kind of soil does 16002 have?

The USDA soil survey maps Gilpin at the center of ZIP 16002: silt loam, well drained, pH about 4.6 (strongly acidic).

Did spring come early in Butler, PA in 2026?

Spring leaf-out near 16002 came on Mar 16 in 2026, 18 days earlier than the 1991–2020 average (Apr 3), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Butler, PA?

Long-day onions: the longest day near 16002 is 15 h 06 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).