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

Planting zone for 16648 — Hollidaysburg, PA

ZIP code 16648 (Hollidaysburg, Blair County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is April 25 and the first fall frost October 20.

Where ZIP 16648 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 25
First frostOct 20
2012 zone6b

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 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Hollidaysburg, 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 Hollidaysburg, PA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 25median — 50% chance of a later frost
Safe for tender plantsMay 14only 10% chance of frost after
First fall frostOctober 20median — 10% chance by Oct 6
Growing season177 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 12 and returns around November 1.

From the NOAA station Altoona 7 Sw, PA — 5 miles away, elevation 1,181 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 16648

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 14 – Mar 28
SpinachSow outdoors · Mar 14 – Apr 4
Broccoli, cabbageStart indoors · Feb 14 – Feb 28
Broccoli, cabbageTransplant · Apr 4 – Apr 18
Onion setsPlant outdoors · Mar 28 – Apr 11
PotatoesPlant outdoors · Apr 4 – Apr 18
LettuceSow outdoors · Mar 28 – Apr 11
Carrots, beetsSow outdoors · Apr 4 – Apr 18
TomatoesStart indoors · Feb 28 – Mar 14
TomatoesTransplant · May 2 – May 16
Peppers, eggplantStart indoors · Feb 14 – Feb 28
Peppers, eggplantTransplant · May 9 – May 23
BeansSow outdoors · May 2 – May 16
Sweet cornSow outdoors · May 2 – May 16
Cucumbers, squashSow outdoors · May 2 – May 16
Fall lettuce, spinachSow outdoors · Aug 25 – Sep 8
GarlicPlant cloves · Oct 6 – Nov 10
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 25) and first fall frost (Oct 20) 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 16648 came on Mar 19 — 15 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 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 Hollidaysburg, PA.

Soil in Hollidaysburg, PA

The soil mapped at the center of ZIP 16648 is Holly — silt loam, poorly drained.

TextureSilt loama good balance for most vegetables
pH6.5neutral; most vegetables like 6.0–7.0
DrainagePoorly drainedconsider raised beds
Organic matter3.5%moderate
Hydrologic groupB/Dmoderate when drained; wet otherwise
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Holly silt loam.

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 16648; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Hollidaysburg, PA

Summer high83 °Faverage high, July
Winter low20 °Faverage low, January
Hot days10days a year at 90 °F or more
Freezing nights127nights a year at 32 °F or less
Growing degree days2,955base 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)
Precipitation41.8 inper year, rain and melted snow
Snowfall38 inper year; 44 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 36 °F, low 20 °F 36°20° JanFebruary: average high 39 °F, low 22 °F 39°22° FebMarch: average high 48 °F, low 28 °F 48°28° MarApril: average high 61 °F, low 38 °F 61°38° AprMay: average high 71 °F, low 49 °F 71°49° MayJune: average high 79 °F, low 58 °F 79°58° JunJuly: average high 83 °F, low 62 °F 83°62° JulAugust: average high 82 °F, low 60 °F 82°60° AugSeptember: average high 75 °F, low 53 °F 75°53° SepOctober: average high 63 °F, low 42 °F 63°42° OctNovember: average high 51 °F, low 33 °F 51°33° NovDecember: average high 40 °F, low 25 °F 40°25° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 2.85 in precipitation, 10.6 in snowfall 2.9❄11 JanFebruary: 2.41 in precipitation, 10.6 in snowfall 2.4❄11 FebMarch: 3.44 in precipitation, 6.6 in snowfall 3.4❄7 MarApril: 3.41 in precipitation, 0.5 in snowfall 3.4❄1 AprMay: 3.88 in precipitation 3.9 MayJune: 3.83 in precipitation 3.8 JunJuly: 3.74 in precipitation 3.7 JulAugust: 3.93 in precipitation 3.9 AugSeptember: 4.44 in precipitation 4.4 SepOctober: 3.47 in precipitation, 0.5 in snowfall 3.5❄1 OctNovember: 3.16 in precipitation, 1.7 in snowfall 3.2❄2 NovDecember: 3.28 in precipitation, 7.5 in snowfall 3.3❄8 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Altoona 7 Sw, PA (5 mi away); precipitation: Altoona 7 Sw, PA (5 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6b.

166026b
Altoona, PA · 5 mi
166036b
Altoona, PA · 6 mi
166936b
Williamsburg, PA · 6 mi
166656b
Newry, PA · 7 mi
166016b
Altoona, PA · 8 mi
166356b
Duncansville, PA · 8 mi
166736b
Roaring Spring, PA · 10 mi
166386b
Entriken, PA · 10 mi

Pennsylvania planting zones →

Questions about 16648

What planting zone is ZIP code 16648?

ZIP code 16648 (Hollidaysburg, 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 Hollidaysburg, PA?

The median last spring frost (32 °F) near 16648 is April 25; after May 14 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Altoona 7 Sw station.

When is the first frost in Hollidaysburg, PA?

The median first fall frost near 16648 is October 20, giving a median frost-free growing season of 177 days.

When should I plant tomatoes in 16648?

Start tomato seeds indoors around Feb 28 – Mar 14 and set transplants outside around May 2 – May 16, one to three weeks after the median last frost.

How much rain and snow does 16648 get?

About 41.8 inches of precipitation a year and 38 inches of snowfall (NOAA 1991–2020 normals, Altoona 7 Sw station).

How hot do summers get in Hollidaysburg, PA?

The average high peaks at 83 °F in July, with about 10 days a year at 90 °F or more.

What kind of soil does 16648 have?

The USDA soil survey maps Holly at the center of ZIP 16648: silt loam, poorly drained, pH about 6.5 (neutral).

Did spring come early in Hollidaysburg, PA in 2026?

Spring leaf-out near 16648 came on Mar 19 in 2026, 15 days earlier than the 1991–2020 average (Apr 3), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Hollidaysburg, PA?

Long-day onions: the longest day near 16648 is 15 h 04 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).