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

Planting zone for 19544 — Mount Aetna, PA

ZIP code 19544 (Mount Aetna, Berks County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is April 20 and the first fall frost October 25.

Where ZIP 19544 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.

Zone7a0 to 5 °F
Coldest night−17.8 to −15 °C
Last frostApr 20
First frostOct 25
2012 zone6b

Was 6b 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 7a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Mount Aetna, 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 Mount Aetna, PA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 20median — 50% chance of a later frost
Safe for tender plantsMay 7only 10% chance of frost after
First fall frostOctober 25median — 10% chance by Oct 10
Growing season185 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 4 and returns around November 5.

From the NOAA station Lebanon 2 W, PA — 11 miles away, elevation 449 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 19544

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 9 – Mar 23
SpinachSow outdoors · Mar 9 – Mar 30
Broccoli, cabbageStart indoors · Feb 9 – Feb 23
Broccoli, cabbageTransplant · Mar 30 – Apr 13
Onion setsPlant outdoors · Mar 23 – Apr 6
PotatoesPlant outdoors · Mar 30 – Apr 13
LettuceSow outdoors · Mar 23 – Apr 6
Carrots, beetsSow outdoors · Mar 30 – Apr 13
TomatoesStart indoors · Feb 23 – Mar 9
TomatoesTransplant · Apr 27 – May 11
Peppers, eggplantStart indoors · Feb 9 – Feb 23
Peppers, eggplantTransplant · May 4 – May 18
BeansSow outdoors · Apr 27 – May 11
Sweet cornSow outdoors · Apr 27 – May 11
Cucumbers, squashSow outdoors · Apr 27 – May 11
Fall lettuce, spinachSow outdoors · Aug 30 – Sep 13
GarlicPlant cloves · Oct 11 – Nov 15
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 20) and first fall frost (Oct 25) 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 19544 came on Mar 24 — 7 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 7a in Pennsylvania

620 plants native to the lower 48 states, recorded in Pennsylvania, and rated by the USDA to survive 0 °F or colder — the bottom of zone 7a. Each links to its USDA PLANTS profile.

Trees 78

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 123

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 212

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 181

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 11

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °FAmerican wisteria50 ft · blooms spring · low shade tolerance · to −3 °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 °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 Mount Aetna, PA.

Soil in Mount Aetna, PA

The soil mapped at the center of ZIP 19544 is Berks — channery loam, well drained. Much of the area is built over (urban land); this is the natural soil underneath.

TextureChannery loama good balance for most vegetables
pH5.1strongly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter3%moderate
Hydrologic groupBwater soaks in moderately
Farmland classNot prime farmlandUSDA classification

Map unit: Urban land-Berks 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 19544; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Mount Aetna, PA

Summer high84 °Faverage high, July
Winter low22 °Faverage low, January
Hot days13days a year at 90 °F or more
Freezing nights120nights a year at 32 °F or less
Growing degree days3,214base 50 °F — the season’s usable heat
Longest day15 h 04 mindaylight on June 21
Shortest day9 h 17 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation48.7 inper year, rain and melted snow
Snowfall30 inper year

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 37 °F, low 22 °F 37°22° JanFebruary: average high 40 °F, low 23 °F 40°23° FebMarch: average high 49 °F, low 31 °F 49°31° MarApril: average high 62 °F, low 40 °F 62°40° AprMay: average high 72 °F, low 51 °F 72°51° MayJune: average high 80 °F, low 60 °F 80°60° JunJuly: average high 84 °F, low 64 °F 84°64° JulAugust: average high 82 °F, low 63 °F 82°63° AugSeptember: average high 76 °F, low 55 °F 76°55° SepOctober: average high 64 °F, low 44 °F 64°44° OctNovember: average high 52 °F, low 34 °F 52°34° NovDecember: average high 42 °F, low 27 °F 42°27° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″6″January: 3.30 in precipitation, 11.3 in snowfall 3.3❄11 JanFebruary: 3.11 in precipitation, 8.7 in snowfall 3.1❄9 FebMarch: 4.14 in precipitation, 5.3 in snowfall 4.1❄5 MarApril: 3.79 in precipitation, 0.4 in snowfall 3.8 AprMay: 3.56 in precipitation 3.6 MayJune: 4.95 in precipitation 5.0 JunJuly: 5.03 in precipitation 5.0 JulAugust: 4.94 in precipitation 4.9 AugSeptember: 4.53 in precipitation 4.5 SepOctober: 4.20 in precipitation 4.2 OctNovember: 3.37 in precipitation, 0.9 in snowfall 3.4❄1 NovDecember: 3.79 in precipitation, 3.6 in snowfall 3.8❄4 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Lebanon 2 W, PA (11 mi away); precipitation: Strausstown, PA (7 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 7a.

170877a
Richland, PA · 2 mi
170677a
Myerstown, PA · 2 mi
195507a
Rehrersburg, PA · 4 mi
195677a
Womelsdorf, PA · 5 mi
195077a
Bethel, PA · 6 mi
170467a
Lebanon, PA · 7 mi
195597a
Strausstown, PA · 8 mi
170887a
Schaefferstown, PA · 8 mi

Pennsylvania planting zones →

Questions about 19544

What planting zone is ZIP code 19544?

ZIP code 19544 (Mount Aetna, PA) is in USDA hardiness zone 7a on the 2023 map: the coldest night of an average winter reaches 0 to 5 °F (−17.8 to −15 °C).

When is the last frost in Mount Aetna, PA?

The median last spring frost (32 °F) near 19544 is April 20; after May 7 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Lebanon 2 W station.

When is the first frost in Mount Aetna, PA?

The median first fall frost near 19544 is October 25, giving a median frost-free growing season of 185 days.

When should I plant tomatoes in 19544?

Start tomato seeds indoors around Feb 23 – Mar 9 and set transplants outside around Apr 27 – May 11, one to three weeks after the median last frost.

How much rain and snow does 19544 get?

About 48.7 inches of precipitation a year and 30 inches of snowfall (NOAA 1991–2020 normals, Strausstown station).

How hot do summers get in Mount Aetna, PA?

The average high peaks at 84 °F in July, with about 13 days a year at 90 °F or more.

What kind of soil does 19544 have?

The USDA soil survey maps Berks at the center of ZIP 19544: channery loam, well drained, pH about 5.1 (strongly acidic).

Did spring come early in Mount Aetna, PA in 2026?

Spring leaf-out near 19544 came on Mar 24 in 2026, 7 days earlier than the 1991–2020 average (Mar 31), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Mount Aetna, PA?

Long-day onions: the longest day near 19544 is 15 h 04 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 19544 change?

Yes. The 2012 USDA map put 19544 in zone 6b; the 2023 map puts it in zone 7a. The newer map uses 1991–2020 data and more weather stations.