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

Planting zone for 17347 — Mount Wolf, PA

ZIP code 17347 (Mount Wolf, York County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is April 26 and the first fall frost October 19.

Where ZIP 17347 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 26
First frostOct 19
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 Wolf, 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 Wolf, PA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 26median — 50% chance of a later frost
Safe for tender plantsMay 13only 10% chance of frost after
First fall frostOctober 19median — 10% chance by Oct 5
Growing season177 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 8 and returns around October 31.

From the NOAA station York 3 Ssw Pump Stn, PA — 10 miles away, elevation 390 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 17347

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 15 – Mar 29
SpinachSow outdoors · Mar 15 – Apr 5
Broccoli, cabbageStart indoors · Feb 15 – Mar 1
Broccoli, cabbageTransplant · Apr 5 – Apr 19
Onion setsPlant outdoors · Mar 29 – Apr 12
PotatoesPlant outdoors · Apr 5 – Apr 19
LettuceSow outdoors · Mar 29 – Apr 12
Carrots, beetsSow outdoors · Apr 5 – Apr 19
TomatoesStart indoors · Mar 1 – Mar 15
TomatoesTransplant · May 3 – May 17
Peppers, eggplantStart indoors · Feb 15 – Mar 1
Peppers, eggplantTransplant · May 10 – May 24
BeansSow outdoors · May 3 – May 17
Sweet cornSow outdoors · May 3 – May 17
Cucumbers, squashSow outdoors · May 3 – May 17
Fall lettuce, spinachSow outdoors · Aug 24 – Sep 7
GarlicPlant cloves · Oct 5 – Nov 9
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 26) and first fall frost (Oct 19) 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 17347 came on Mar 21 — 6 days earlier than the 1991–2020 average (Mar 27).

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 Wolf, PA.

Soil in Mount Wolf, PA

The soil mapped at the center of ZIP 17347 is Mt. Airy — channery silt loam, somewhat excessively drained.

TextureChannery silt loama good balance for most vegetables
pH5.4strongly acidic; most vegetables like 6.0–7.0
DrainageSomewhat excessively drainednatural drainage class
Organic matter2%moderate
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Mt. Airy and Manor soils, 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 17347; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Mount Wolf, PA

Summer high88 °Faverage high, July
Winter low21 °Faverage low, January
Hot days28days a year at 90 °F or more
Freezing nights120nights a year at 32 °F or less
Growing degree days3,556base 50 °F — the season’s usable heat
Longest day15 h 01 mindaylight on June 21
Shortest day9 h 19 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation46.5 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 41 °F, low 21 °F 41°21° JanFebruary: average high 45 °F, low 23 °F 45°23° FebMarch: average high 55 °F, low 30 °F 55°30° MarApril: average high 67 °F, low 40 °F 67°40° AprMay: average high 77 °F, low 50 °F 77°50° MayJune: average high 84 °F, low 59 °F 84°59° JunJuly: average high 88 °F, low 63 °F 88°63° JulAugust: average high 86 °F, low 62 °F 86°62° AugSeptember: average high 80 °F, low 55 °F 80°55° SepOctober: average high 68 °F, low 43 °F 68°43° OctNovember: average high 56 °F, low 33 °F 56°33° NovDecember: average high 45 °F, low 26 °F 45°26° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 3.21 in precipitation 3.2 JanFebruary: 2.92 in precipitation 2.9 FebMarch: 4.05 in precipitation 4.0 MarApril: 3.57 in precipitation 3.6 AprMay: 4.23 in precipitation 4.2 MayJune: 4.45 in precipitation 4.5 JunJuly: 4.88 in precipitation 4.9 JulAugust: 3.83 in precipitation 3.8 AugSeptember: 4.69 in precipitation 4.7 SepOctober: 4.01 in precipitation 4.0 OctNovember: 3.19 in precipitation 3.2 NovDecember: 3.49 in precipitation 3.5 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: York 3 Ssw Pump Stn, PA (10 mi away); precipitation: Mount Wolf 1.0 Se, PA (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 7a.

174067a
York, PA · 3 mi
173187a
Emigsville, PA · 3 mi
173457a
Manchester, PA · 3 mi
175027a
Bainbridge, PA · 4 mi
174057a
York, PA · 5 mi
175477a
Marietta, PA · 5 mi
173587a
Rossville, PA · 5 mi
175507a
Maytown, PA · 5 mi

Pennsylvania planting zones →

Questions about 17347

What planting zone is ZIP code 17347?

ZIP code 17347 (Mount Wolf, 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 Wolf, PA?

The median last spring frost (32 °F) near 17347 is April 26; after May 13 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, York 3 Ssw Pump Stn station.

When is the first frost in Mount Wolf, PA?

The median first fall frost near 17347 is October 19, giving a median frost-free growing season of 177 days.

When should I plant tomatoes in 17347?

Start tomato seeds indoors around Mar 1 – Mar 15 and set transplants outside around May 3 – May 17, one to three weeks after the median last frost.

How much rain and snow does 17347 get?

About 46.5 inches of precipitation a year (NOAA 1991–2020 normals, Mount Wolf 1.0 Se station).

How hot do summers get in Mount Wolf, PA?

The average high peaks at 88 °F in July, with about 28 days a year at 90 °F or more.

What kind of soil does 17347 have?

The USDA soil survey maps Mt. Airy at the center of ZIP 17347: channery silt loam, somewhat excessively drained, pH about 5.4 (strongly acidic).

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

Spring leaf-out near 17347 came on Mar 21 in 2026, 6 days earlier than the 1991–2020 average (Mar 27), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Mount Wolf, PA?

Long-day onions: the longest day near 17347 is 15 h 01 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 17347 change?

Yes. The 2012 USDA map put 17347 in zone 6b; the 2023 map puts it in zone 7a. The newer map uses 1991–2020 data and more weather stations.