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

Planting zone for 16868 — Pine Grove Mills, PA

ZIP code 16868 (Pine Grove Mills, Centre County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is April 20 and the first fall frost October 26.

Where ZIP 16868 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 20
First frostOct 26
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 Pine Grove Mills, 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 Pine Grove Mills, 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 6only 10% chance of frost after
First fall frostOctober 26median — 10% chance by Oct 10
Growing season187 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 8 and returns around November 5.

From the NOAA station State College, PA — 5 miles away, elevation 1,171 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 16868

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 31 – Sep 14
GarlicPlant cloves · Oct 12 – Nov 16
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 20) and first fall frost (Oct 26) 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 16868 came on Mar 31 — 7 days earlier than the 1991–2020 average (Apr 7).

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 Pine Grove Mills, PA.

Soil in Pine Grove Mills, PA

The soil mapped at the center of ZIP 16868 is Laidig — channery loam, well drained.

TextureChannery loama good balance for most vegetables
pH4.6strongly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter2.5%moderate
Hydrologic groupBwater soaks in moderately
Farmland classNot prime farmlandUSDA classification

Map unit: Laidig extremely stony loam, steep.

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 16868; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Pine Grove Mills, PA

Summer high81 °Faverage high, July
Winter low21 °Faverage low, January
Hot days6days a year at 90 °F or more
Freezing nights122nights a year at 32 °F or less
Growing degree days2,874base 50 °F — the season’s usable heat
Longest day15 h 06 mindaylight on June 21
Shortest day9 h 15 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation41.5 inper year, rain and melted snow
Snowfall44 inper year; 46 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 21 °F 34°21° JanFebruary: average high 37 °F, low 22 °F 37°22° FebMarch: average high 46 °F, low 28 °F 46°28° MarApril: average high 59 °F, low 39 °F 59°39° AprMay: average high 69 °F, low 50 °F 69°50° MayJune: average high 77 °F, low 59 °F 77°59° JunJuly: average high 81 °F, low 63 °F 81°63° JulAugust: average high 79 °F, low 62 °F 79°62° AugSeptember: average high 72 °F, low 54 °F 72°54° SepOctober: average high 61 °F, low 43 °F 61°43° OctNovember: average high 49 °F, low 34 °F 49°34° NovDecember: average high 38 °F, low 26 °F 38°26° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 2.92 in precipitation, 11.3 in snowfall 2.9❄11 JanFebruary: 2.46 in precipitation, 11.6 in snowfall 2.5❄12 FebMarch: 3.38 in precipitation, 9.4 in snowfall 3.4❄9 MarApril: 3.51 in precipitation, 0.9 in snowfall 3.5❄1 AprMay: 3.64 in precipitation 3.6 MayJune: 4.09 in precipitation 4.1 JunJuly: 3.79 in precipitation 3.8 JulAugust: 4.16 in precipitation 4.2 AugSeptember: 3.95 in precipitation 4.0 SepOctober: 3.46 in precipitation, 0.4 in snowfall 3.5 OctNovember: 2.99 in precipitation, 2.6 in snowfall 3.0❄3 NovDecember: 3.18 in precipitation, 7.6 in snowfall 3.2❄8 Dec

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

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6b.

168656b
Pennsylvania Furnace, PA · 3 mi
168016b
State College, PA · 5 mi
168046b
State College, PA · 5 mi
168056b
State College, PA · 5 mi
166696b
Petersburg, PA · 5 mi
168026b
University Park, PA · 5 mi
168036b
State College, PA · 6 mi
168276b
Boalsburg, PA · 7 mi

Pennsylvania planting zones →

Questions about 16868

What planting zone is ZIP code 16868?

ZIP code 16868 (Pine Grove Mills, 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 Pine Grove Mills, PA?

The median last spring frost (32 °F) near 16868 is April 20; after May 6 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, State College station.

When is the first frost in Pine Grove Mills, PA?

The median first fall frost near 16868 is October 26, giving a median frost-free growing season of 187 days.

When should I plant tomatoes in 16868?

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 16868 get?

About 41.5 inches of precipitation a year and 44 inches of snowfall (NOAA 1991–2020 normals, State College station).

How hot do summers get in Pine Grove Mills, PA?

The average high peaks at 81 °F in July, with about 6 days a year at 90 °F or more.

What kind of soil does 16868 have?

The USDA soil survey maps Laidig at the center of ZIP 16868: channery loam, well drained, pH about 4.6 (strongly acidic).

Did spring come early in Pine Grove Mills, PA in 2026?

Spring leaf-out near 16868 came on Mar 31 in 2026, 7 days earlier than the 1991–2020 average (Apr 7), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Pine Grove Mills, PA?

Long-day onions: the longest day near 16868 is 15 h 06 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).