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

Planting zone for 15084 — Tarentum, PA

ZIP code 15084 (Tarentum, Allegheny County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is April 16 and the first fall frost November 2.

Where ZIP 15084 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.

Zone6b−5 to 0 °F
Coldest night−20.6 to −17.8 °C
Last frostApr 16
First frostNov 2
2012 zone6a

Was 6a 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 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Tarentum, 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 Tarentum, PA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 16median — 50% chance of a later frost
Safe for tender plantsMay 2only 10% chance of frost after
First fall frostNovember 2median — 10% chance by Oct 20
Growing season199 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 3 and returns around November 14.

From the NOAA station Natrona Lock 4, PA — 4 miles away, elevation 761 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 15084

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 5 – Mar 19
SpinachSow outdoors · Mar 5 – Mar 26
Broccoli, cabbageStart indoors · Feb 5 – Feb 19
Broccoli, cabbageTransplant · Mar 26 – Apr 9
Onion setsPlant outdoors · Mar 19 – Apr 2
PotatoesPlant outdoors · Mar 26 – Apr 9
LettuceSow outdoors · Mar 19 – Apr 2
Carrots, beetsSow outdoors · Mar 26 – Apr 9
TomatoesStart indoors · Feb 19 – Mar 5
TomatoesTransplant · Apr 23 – May 7
Peppers, eggplantStart indoors · Feb 5 – Feb 19
Peppers, eggplantTransplant · Apr 30 – May 14
BeansSow outdoors · Apr 23 – May 7
Sweet cornSow outdoors · Apr 23 – May 7
Cucumbers, squashSow outdoors · Apr 23 – May 7
Fall lettuce, spinachSow outdoors · Sep 7 – Sep 21
GarlicPlant cloves · Oct 19 – Nov 23
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 16) and first fall frost (Nov 2) 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 15084 came on Mar 15 — 15 days earlier than the 1991–2020 average (Mar 30).

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 6b in Pennsylvania

605 plants native to the lower 48 states, recorded in Pennsylvania, and rated by the USDA to survive −5 °F or colder — the bottom of zone 6b. 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 122

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 209

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 173

American beachgrass2.5 ft · blooms spring · high shade tolerance · to −28 °Farctic brome3 ft · blooms early summer · low shade tolerance · to −33 °FAtlantic mannagrass3 ft · blooms summer · low shade tolerance · to −8 °Fautumn bluegrass1.5 ft · blooms late spring · medium shade tolerance · to −8 °Fawlfruit sedge4 ft · blooms mid spring · low shade tolerance · to −38 °FBailey's sedge2.1 ft · blooms late spring · low shade tolerance · to −33 °F

Vines 10

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 °Fgraybark grape50 ft · blooms late spring · medium shade tolerance · to −8 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °Fsummer grape30 ft · blooms late spring · low shade tolerance · to −23 °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 Tarentum, PA.

Soil in Tarentum, PA

The soil mapped at the center of ZIP 15084 is Gilpin — slightly decomposed plant material, well drained.

TextureSlightly decomposed plant materialtop layer
pH4.3strongly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter69%high
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Gilpin, Weikert, Culleoka channery silt loams and 25 to 80 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 15084; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Tarentum, PA

Summer high83 °Faverage high, July
Winter low21 °Faverage low, January
Hot days14days a year at 90 °F or more
Freezing nights117nights a year at 32 °F or less
Growing degree days3,141base 50 °F — the season’s usable heat
Longest day15 h 05 mindaylight on June 21
Shortest day9 h 16 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation42.2 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 37 °F, low 21 °F 37°21° JanFebruary: average high 40 °F, low 21 °F 40°21° FebMarch: average high 50 °F, low 27 °F 50°27° MarApril: average high 63 °F, low 38 °F 63°38° AprMay: average high 72 °F, low 50 °F 72°50° MayJune: average high 80 °F, low 59 °F 80°59° JunJuly: average high 83 °F, low 63 °F 83°63° JulAugust: average high 82 °F, low 62 °F 82°62° AugSeptember: average high 76 °F, low 55 °F 76°55° SepOctober: average high 64 °F, low 43 °F 64°43° OctNovember: average high 52 °F, low 33 °F 52°33° NovDecember: average high 41 °F, low 26 °F 41°26° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 3.12 in precipitation 3.1 JanFebruary: 2.79 in precipitation 2.8 FebMarch: 3.27 in precipitation 3.3 MarApril: 3.58 in precipitation 3.6 AprMay: 3.90 in precipitation 3.9 MayJune: 4.34 in precipitation 4.3 JunJuly: 4.26 in precipitation 4.3 JulAugust: 3.55 in precipitation 3.5 AugSeptember: 3.99 in precipitation 4.0 SepOctober: 3.09 in precipitation 3.1 OctNovember: 3.09 in precipitation 3.1 NovDecember: 3.26 in precipitation 3.3 Dec

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

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6b.

150766b
Russellton, PA · 2 mi
150306b
Creighton, PA · 3 mi
150756b
Rural Ridge, PA · 3 mi
150146b
Brackenridge, PA · 4 mi
150246b
Cheswick, PA · 4 mi
150066b
Bairdford, PA · 4 mi
150656b
Natrona Heights, PA · 4 mi
150696b
New Kensington, PA · 5 mi

Pennsylvania planting zones →

Questions about 15084

What planting zone is ZIP code 15084?

ZIP code 15084 (Tarentum, PA) is in USDA hardiness zone 6b on the 2023 map: the coldest night of an average winter reaches −5 to 0 °F (−20.6 to −17.8 °C).

When is the last frost in Tarentum, PA?

The median last spring frost (32 °F) near 15084 is April 16; after May 2 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Natrona Lock 4 station.

When is the first frost in Tarentum, PA?

The median first fall frost near 15084 is November 2, giving a median frost-free growing season of 199 days.

When should I plant tomatoes in 15084?

Start tomato seeds indoors around Feb 19 – Mar 5 and set transplants outside around Apr 23 – May 7, one to three weeks after the median last frost.

How much rain and snow does 15084 get?

About 42.2 inches of precipitation a year (NOAA 1991–2020 normals, Natrona Lock 4 station).

How hot do summers get in Tarentum, PA?

The average high peaks at 83 °F in July, with about 14 days a year at 90 °F or more.

What kind of soil does 15084 have?

The USDA soil survey maps Gilpin at the center of ZIP 15084: slightly decomposed plant material, well drained, pH about 4.3 (strongly acidic).

Did spring come early in Tarentum, PA in 2026?

Spring leaf-out near 15084 came on Mar 15 in 2026, 15 days earlier than the 1991–2020 average (Mar 30), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Tarentum, PA?

Long-day onions: the longest day near 15084 is 15 h 05 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 15084 change?

Yes. The 2012 USDA map put 15084 in zone 6a; the 2023 map puts it in zone 6b. The newer map uses 1991–2020 data and more weather stations.