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

Planting zone for Butler, PA

Butler, PA is in USDA zones 6a to 6b across its 3 ZIP codes. The median last spring frost is May 7 and the first fall frost October 14.

Butler on the zone map

Outlined: its 2 ZIP code areas · 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.

Zones6a–6b−10 to 0 °F
ZIP codes3
Last frostMay 7
First frostOct 14
Growing season159 days

6a 2 ZIPs   6b 1 ZIP

Frost forecast — next 7 nights

live from the National Weather Service

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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, 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 Butler

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 16003 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

American basswood100 ft · blooms late spring · low shade tolerance · to −46 °FAmerican beech80 ft · blooms mid spring · low shade tolerance · to −44 °FAmerican chestnut115 ft · blooms early summer · high shade tolerance · to −33 °FAmerican elm120 ft · blooms early spring · medium shade tolerance · to −46 °FAmerican sycamore100 ft · blooms spring · medium shade tolerance · to −34 °Farborvitae50 ft · blooms mid spring · medium shade tolerance · to −33 °F

Shrubs 121

alderleaf buckthorn3 ft · blooms late spring · low shade tolerance · to −33 °FAllegheny serviceberry35 ft · blooms early spring · low shade tolerance · to −38 °Falternateleaf dogwood25 ft · blooms mid spring · low shade tolerance · to −47 °FAmerican black currant3 ft · blooms early spring · to −46 °FAmerican hazelnut10 ft · blooms spring · medium shade tolerance · to −33 °FAmerican holly40 ft · blooms mid spring · low shade tolerance · to −20 °F

Wildflowers & perennials 207

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °FAmerican bur-reed3 ft · blooms indeterminate · medium shade tolerance · to −33 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °FAmerican licorice4 ft · blooms late spring · medium shade tolerance · to −38 °FAmerican lotus3 ft · blooms mid summer · high shade tolerance · to −36 °FAmerican pokeweed7 ft · blooms mid summer · low shade tolerance · to −33 °F

Grasses 170

American beachgrass2.5 ft · blooms spring · high shade tolerance · to −28 °Farctic brome3 ft · blooms early summer · low shade tolerance · to −33 °Fawlfruit sedge4 ft · blooms mid spring · low shade tolerance · to −38 °FBailey's sedge2.1 ft · blooms late spring · low shade tolerance · to −33 °Fbeaked spikerush3 ft · blooms late spring · high shade tolerance · to −28 °FBebb's sedge3 ft · blooms late spring · low shade tolerance · to −38 °F

Vines 9

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °Fdevil's darning needles15 ft · blooms mid summer · medium shade tolerance · to −38 °Ffrost grape83 ft · blooms late spring · medium shade tolerance · to −23 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °Fsummer grape30 ft · blooms late spring · low shade tolerance · to −23 °Ftrumpet creeper2 ft · blooms summer · high shade tolerance · to −13 °F

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 16003 is Ernest — silt loam, moderately well drained. Much of the area is built over (urban land); this is the natural soil underneath.

TextureSilt loama good balance for most vegetables
pH5.4strongly acidic; most vegetables like 6.0–7.0
DrainageModerately well drainednatural drainage class
Organic matter3%moderate
Hydrologic groupC/Dslow when drained; wet otherwise
Farmland classNot prime farmlandUSDA classification

Map unit: Urban land-Ernest complex, 0 to 8 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 16003; 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 07 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 (2 mi away); precipitation: Butler 2 Sw, PA (2 mi away). Daylight is calculated from latitude.

ZIP codes in Butler

160016a
−10 to −5 °F
160026a
−10 to −5 °F
160036b
−5 to 0 °F

Pennsylvania planting zones →

Questions about Butler

What planting zone is Butler, PA?

Butler, PA is in USDA hardiness zones 6a to 6b on the 2023 map (6a: −10 to −5 °F; 6b: −5 to 0 °F).

When is the last frost in Butler, PA?

The median last spring frost is May 7 and the median first fall frost is October 14 (NOAA 1991–2020 normals, Butler 2 Sw station).

When can I plant a garden in Butler, PA?

Cool-season crops like peas and spinach go in around Mar 26 – Apr 16; tomatoes, peppers, beans and squash after about May 14, once frost risk has passed.

What kind of onions grow in Butler, PA?

Long-day onions: the longest day is 15 h 07 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

How much rain and snow does Butler, PA get?

About 43.2 inches of precipitation a year and 35 inches of snowfall (NOAA 1991–2020 normals).