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

Planting zone for 15437 — Farmington, PA

ZIP code 15437 (Farmington, Fayette County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is May 19 and the first fall frost October 1.

Where ZIP 15437 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 19
First frostOct 1
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 Farmington, 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 Farmington, PA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 19median — 50% chance of a later frost
Safe for tender plantsJune 2only 10% chance of frost after
First fall frostOctober 1median — 10% chance by Sep 18
Growing season135 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 5 and returns around October 10.

From the NOAA station Chalk Hill 2 Ene, PA — 4 miles away, elevation 1,982 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 15437

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 7 – Apr 21
SpinachSow outdoors · Apr 7 – Apr 28
Broccoli, cabbageStart indoors · Mar 10 – Mar 24
Broccoli, cabbageTransplant · Apr 28 – May 12
Onion setsPlant outdoors · Apr 21 – May 5
PotatoesPlant outdoors · Apr 28 – May 12
LettuceSow outdoors · Apr 21 – May 5
Carrots, beetsSow outdoors · Apr 28 – May 12
TomatoesStart indoors · Mar 24 – Apr 7
TomatoesTransplant · May 26 – Jun 9
Peppers, eggplantStart indoors · Mar 10 – Mar 24
Peppers, eggplantTransplant · Jun 2 – Jun 16
BeansSow outdoors · May 26 – Jun 9
Sweet cornSow outdoors · May 26 – Jun 9
Cucumbers, squashSow outdoors · May 26 – Jun 9
Fall lettuce, spinachSow outdoors · Aug 6 – Aug 20
GarlicPlant cloves · Sep 17 – Oct 22
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 19) and first fall frost (Oct 1) 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 15437 came on Mar 15 — 16 days earlier than the 1991–2020 average (Mar 31).

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 Farmington, PA.

Soil in Farmington, PA

The soil mapped at the center of ZIP 15437 is Gilpin — slightly decomposed plant material, well drained.

TextureSlightly decomposed plant materialtop layer
pH5.0strongly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter72%high
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Gilpin channery silt loam, 15 to 25 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 15437; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Farmington, PA

Summer high79 °Faverage high, July
Winter low15 °Faverage low, January
Hot days0days a year at 90 °F or more
Freezing nights138nights a year at 32 °F or less
Growing degree days2,131base 50 °F — the season’s usable heat
Longest day15 h 00 mindaylight on June 21
Shortest day9 h 21 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation55.7 inper year, rain and melted snow
Snowfall89 inper year; 79 days with snow on the ground

Average high and low, by month

0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 34 °F, low 15 °F 34°15° JanFebruary: average high 38 °F, low 17 °F 38°17° FebMarch: average high 48 °F, low 24 °F 48°24° MarApril: average high 61 °F, low 33 °F 61°33° AprMay: average high 69 °F, low 43 °F 69°43° MayJune: average high 75 °F, low 52 °F 75°52° JunJuly: average high 79 °F, low 56 °F 79°56° JulAugust: average high 77 °F, low 54 °F 77°54° AugSeptember: average high 71 °F, low 47 °F 71°47° SepOctober: average high 61 °F, low 36 °F 61°36° OctNovember: average high 49 °F, low 27 °F 49°27° NovDecember: average high 39 °F, low 20 °F 39°20° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″6″January: 4.56 in precipitation, 26.9 in snowfall 4.6❄27 JanFebruary: 4.11 in precipitation, 18 in snowfall 4.1❄18 FebMarch: 5.02 in precipitation, 15.5 in snowfall 5.0❄16 MarApril: 4.72 in precipitation, 3.7 in snowfall 4.7❄4 AprMay: 5.20 in precipitation 5.2 MayJune: 5.74 in precipitation 5.7 JunJuly: 4.65 in precipitation 4.7 JulAugust: 4.54 in precipitation 4.5 AugSeptember: 4.70 in precipitation 4.7 SepOctober: 3.80 in precipitation, 0.9 in snowfall 3.8❄1 OctNovember: 4.13 in precipitation, 6.2 in snowfall 4.1❄6 NovDecember: 4.51 in precipitation, 17.6 in snowfall 4.5❄18 Dec

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

Nearby ZIP codes

2 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 15437

What planting zone is ZIP code 15437?

ZIP code 15437 (Farmington, 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 Farmington, PA?

The median last spring frost (32 °F) near 15437 is May 19; after June 2 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Chalk Hill 2 Ene station.

When is the first frost in Farmington, PA?

The median first fall frost near 15437 is October 1, giving a median frost-free growing season of 135 days.

When should I plant tomatoes in 15437?

Start tomato seeds indoors around Mar 24 – Apr 7 and set transplants outside around May 26 – Jun 9, one to three weeks after the median last frost.

How much rain and snow does 15437 get?

About 55.7 inches of precipitation a year and 89 inches of snowfall (NOAA 1991–2020 normals, Chalk Hill 2 Ene station).

How hot do summers get in Farmington, PA?

The average high peaks at 79 °F in July, with about 0 days a year at 90 °F or more.

What kind of soil does 15437 have?

The USDA soil survey maps Gilpin at the center of ZIP 15437: slightly decomposed plant material, well drained, pH about 5.0 (strongly acidic).

Did spring come early in Farmington, PA in 2026?

Spring leaf-out near 15437 came on Mar 15 in 2026, 16 days earlier than the 1991–2020 average (Mar 31), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Farmington, PA?

Intermediate onions: the longest day near 15437 is 15 h 00 min, so day-neutral types bulb best; long-day varieties may not bulb fully.