USDA zone 7a in Pennsylvania

0 to 5 °F avg. annual extreme minimum · 50 locations in this group · NOAA 1991–2020 normals

USDA plant hardiness zone 7a covers 50 locations across Pennsylvania (average annual extreme minimum 0 to 5 °F): Adamstown, PA, Avondale, PA, Bethlehem, PA, Blue Bell, PA, Boiling Springs, PA, Carlisle, PA, and 44 more. Average last spring frost across this group ranges April 1 (Susquehanna Trails) to May 8 (Lake), and growing seasons run 160–221 days (Lake to Susquehanna Trails) — even within one state, because hardiness sets winter survival, not planting dates. The table below gives every Pennsylvania location's own frost dates; the printable planting calendar uses Gilbertsville, this group's median-season location.

USDA zone
7a0 to 5 °F
Last frost range
Apr 1–May 8avg, 32°F
First frost range
Oct 10–Nov 10avg, 32°F
Growing season range
160–221days

Locations in this group

Every location below shares this zone and a nearby weather station, but keeps its own frost dates — find your town for its own numbers, or use the ZIP planner on the home page for an instant personalized answer.

Own frost dates per location.
LocationAlso coversNearest stationLast frostFirst frostSeason (days)
AdamstownStouchsburg, Denver, Sinking Spring, Reinholds, Robesonia, Wernersville, +3 moreBlue Marsh LakeApr 26Oct 19176
AvondaleAvondale 2 NApr 19Oct 26189
BethlehemAllentown, Breinigsville, Emmaus, Schnecksville, Wescosville, Middletown, +11 moreAllentown Intl ApApr 20Oct 24184
Blue BellNorristown, Spring House, North WalesNorristownApr 8Oct 31203
Boiling SpringsGettysburg, Cashtown, McKnightstown, Aspers, Arendtsville, Idaville, +2 moreBiglervilleApr 15Oct 27194
CarlisleSchlusserCarlisle WtpApr 23Oct 18177
Carroll ValleyWalkersville, Taneytown, Thurmont, Libertytown, Emmitsburg, Union Bridge, +4 moreEmmitsburg 2 SeApr 22Oct 20179
ChambersburgFort Loudon, Waynesboro, Fayetteville, Marion, Scotland, Mont Alto, +3 moreChambersburg 1 EseApr 18Oct 25188
DowningtownWest Chester, UnionvilleW Chester 2 NwApr 26Oct 18174
East YorkTyler Run, Jacobus, Dallastown, WindsorYork 3 Ssw Pump StnApr 26Oct 19177
ElversonHopewell MorgantownApr 16Oct 27193
ErieNorthwest Harborcreek, LakeErie Intl ApApr 26Nov 4192
Fort Indiantown GapCornwall, Campbelltown, Schaefferstown, Fredericksburg, Annville, Quentin, +6 moreLebanon 2 WApr 20Oct 25185
GeorgetownNottingham, Kirkwood, Oxford, Wakefield, Rising Sun, Quarryville, +4 moreOctoraro LakeApr 26Oct 22179
Gilbertsville *Pottsgrove, Kenilworth, New Berlinville, Boyertown, Spring Mount, Bechtelsville, +1 morePottstown Limerick ApApr 20Oct 23186
GlenmooreGlenmooreApr 11Nov 1205
GranvilleMexico, Burnham, Atkinson Mills, Loysville, Mattawana, Port Royal, +5 moreLewistownApr 21Oct 24185
HarrisburgColonial Park, Linglestown, Schlusser, Marysville, Camp Hill, Lemoyne, +8 moreHarrisburg 1 NeApr 15Oct 23189
HellertownPalmer Heights, Riegelsville, Coopersburg, Bloomsbury, Glendon, DeSales UniversitySpringtown 1 NneApr 21Oct 22184
HersheyElizabethtown, Middletown, Steelton, Bainbridge, Valley Green, Hummelstown, +5 moreMiddletown Harrisburg Intl ApApr 9Nov 2206
HorshamHatboroPhiladelphia Ne ApApr 4Nov 7216
HuntingdonMarklesburg, Allenport, Rockhill, Saltillo, Shirleysburg, Newton HamiltonRaystown Lake 2Apr 19Oct 28191
King of PrussiaPhoenixville, Exton, Trooper, Wayne, Frazer, Villanova, +12 morePhoenixville 1 EApr 18Oct 27192
LakeSpringboro 3 WnwMay 8Oct 16160
LancasterLeola, Brownstown, Millersville, Lampeter, Witmer, Akron, +4 moreLancaster 2ne Fltr PltApr 19Oct 24186
LandisburgBloserville 1 NApr 18Oct 26191
LansdaleSkippack, SchwenksvilleGraterford 1 EApr 24Oct 15173
LevittownRichboro, Churchville, Newtown, Trevose, Langhorne, IvylandNeshaminy FallsApr 21Oct 25185
LinglestownSkyline ViewDehart DamMay 1Oct 16168
MaytownColumbia, Mount Joy, Lititz, Washington Boro, Rheems, Manheim, +5 moreLandisville 2 NwApr 30Oct 10162
McKees RocksLeetsdale, EmsworthPittsburgh Intl ApApr 23Oct 23181
MillersburgSelinsgrove 2 SApr 25Oct 22178
MontgomeryvillePlumsteadville, Doylestown, New BritainDoylestown ApApr 13Oct 30198
MontgomeryvilleHarleysville, Plumsteadville, Quakertown, Chalfont, Sellersville, Souderton, +11 moreSellersvilleApr 26Oct 17175
MontgomeryvilleWillow Grove NasApr 11Nov 1205
NeedmoreWarfordsburgEverettApr 27Oct 17170
NemacolinEdenborn, BuffingtonUniontown 1 NeApr 30Oct 18171
New MorganGeorgetown, Ephrata, Gap, Bowmansville, New Holland, Intercourse, +7 moreNew Holland 2 SeApr 14Nov 1198
PittsburghPittsburgh Allegheny Co ApApr 18Oct 28193
PittsburghEmsworth L/d Ohio RvrApr 24Oct 27186
PlainfieldNewville, East Waterford, Shippensburg University, Newburg, Shirleysburg, Orrstown, +1 moreShippensburgApr 19Oct 24188
PlumsteadvilleMilford, Frenchtown, StocktonBucksvilleApr 29Oct 16170
ReadingNew Morgan, Wyomissing, Blandon, Alleghenyville, Jacksonwald, Birdsboro, +8 moreReading Spaatz FldApr 14Oct 29197
Susquehanna TrailsConestoga, Fawn Grove, Felton, WindsorSafe Harbor DamApr 1Nov 10221
ThorndaleSouth Coatesville, Glenmoore, Parkesburg, Pomeroy, SadsburyvilleCoatesville 2 WApr 19Oct 25190
Three SpringsAltoona Blair Co ApApr 23Oct 21177
ToptonRodale Rsch CtrApr 26Oct 14171
West HamburgFriedensburg, Auburn, Summit Station, Virginville, Bethel, Cressona, +8 moreHamburgApr 16Oct 25189
Wilkes-BarreDuryea, Old ForgeWilkes-barre Intl ApApr 23Oct 20178
YorkShiloh, Emigsville, Lake Meade, Seven Valleys, Loganville, Spring Grove, +5 moreYork ApApr 27Oct 18174

* Gilbertsville is this group's median-season location — the calendar below is computed from its data.

Data: NOAA NCEI U.S. Climate Normals 1991–2020 (public domain) and USDA Plant Hardiness Zone Map 2023. Planting windows synthesized from U.S. Cooperative Extension guides.

Planting calendar (Gilbertsville, representative)

Computed from Gilbertsville's average frost dates — the median-season location in this Pennsylvaniazone 7a group. hatched = start seeds indoors, solid green = plant out, teal = a fall sowing, and the terracotta dot marks the estimated first harvest. Ranges are extension-guide planning guidance, not guarantees — your own location's dates may run a week or two earlier or later (see the table above).

  • Start indoors
  • Plant out
  • Fall sowing
  • First harvest
Planting windows for Gilbertsville (Pennsylvania, zone 7a), this group's representative location.
CropFrost toleranceStart indoorsPlant outFirst harvestFall plantingSeason fit
TomatoTenderFeb 23 – Mar 9Apr 27 – May 4Jun 26 – Jul 16matures comfortably
PepperVery tenderFeb 9 – Feb 23May 4 – May 11Jul 3 – Aug 2matures comfortably
CucumberTenderMar 23 – Mar 30Apr 27 – May 4Jun 16 – Jul 6matures comfortably
Summer squash / zucchiniTenderApr 27 – May 4Jun 11 – Jun 26matures comfortably
Bush beanTenderApr 27 – May 4Jun 16 – Jun 26Aug 24 – Sep 3matures comfortably
Sweet cornTenderApr 20 – May 4Jun 19 – Jul 19matures comfortably
BasilVery tenderMar 9 – Mar 23Apr 27 – May 4May 27 – Jun 11matures comfortably
LettuceHalf-hardyMar 9 – Mar 23Mar 23 – Apr 6May 7 – May 22Aug 10 – Aug 25matures comfortably
PeaHardyMar 9 – Mar 23May 3 – May 18Jul 31 – Aug 15matures comfortably
SpinachHardyMar 9 – Mar 23Apr 18 – Apr 28Aug 20 – Aug 30matures comfortably
CarrotHalf-hardyMar 30 – Apr 6May 29 – Jun 18Jul 21 – Aug 10matures comfortably
BroccoliHalf-hardyFeb 23 – Mar 9Mar 23 – Apr 6May 17 – Jun 6Jul 26 – Aug 15matures comfortably

Which crops fit this growing season

Using Gilbertsville's own 186-day growing season (32°F, NOAA 1991–2020 median) against each crop's real days-to-maturity range: 12 of 12 crops mature here with comfortable margin. A different location in the table above with a longer or shorter season will get a different mix — the ZIP planner on the home page gives your own.

Frost & freeze dates (Gilbertsville)

From NOAA's 1991–2020 Climate Normals at station USW00054782. The median (p50) is the average date; the 90%-safe column is the date the freeze has passed in about 9 years out of 10 — the conservative date to plant after or harvest before.

Freeze probabilities by temperature threshold (MM/DD, NOAA 1991–2020), Gilbertsville.
ThresholdLast spring — avgLast spring — 90%-safeFirst fall — avgFirst fall — 90%-safeSeason (days)
36°FMay 2May 19Oct 12Oct 26162
32°F (freeze)Apr 20May 6Oct 23Nov 5186
28°FApr 6Apr 21Nov 3Nov 18212
24°FMar 26Apr 8Nov 15Dec 3235

Growing degree days

Growing degree days (GDD) accumulate warmth above a base temperature over the year — a better predictor of crop development than the calendar alone. This group's median GDD (base 50°F) across all 50 locations is 3,230; Gilbertsville's own reading is shown below.

Annual growing degree days for Gilbertsville (°F·days, NOAA 1991–2020).
Model°F·daysUsed for
Base 50°F (warm-season)3,108standard warm-season base (tomato, corn, beans)
Base 40°F (cool-season)5,394cool-season crops (brassicas, greens)

Hardiness zone 7a in Pennsylvania

Zone 7a means an average annual extreme minimum winter temperature of about 0 to 5 °F on the USDA's 2023 map — the number that tells you which perennials, shrubs, and trees reliably survive an average winter here. It does not set your planting dates, which come from the frost calendar above. Pennsylvania spans 7 hardiness zones in this dataset — see all Pennsylvania locations for the full range, including zones5a, 5b, 6a, 6b, 7b, 8a.

Explore zone 7a in other states at zone 7a, or see all USDA hardiness zones.

Frequently asked questions

What does USDA hardiness zone 7a mean in Pennsylvania?
Zone 7a means an average annual extreme minimum winter temperature of 0 to 5 °F — the standard USDA measure of which perennials survive winter. 50 locations in Pennsylvania fall in this zone. It does not set planting dates; see the frost calendar below for that.
Where in Pennsylvania's zone 7a is the growing season longest?
Susquehanna Trails runs the longest season on this page at about 221 days; Lake is shortest at about 160 days — they share the same hardiness zone, but they sit at different weather stations, so their frost calendars differ.
When should I plant tomatoes in Pennsylvania's zone 7a?
Using Gilbertsville's frost dates (this page's median-season location): start seeds indoors about Feb 23 – Mar 9, then transplant outside about Apr 27 – May 4. Your own location in the table above may differ by a week or two — use the ZIP planner on the home page for your exact station's dates.
Does every location in Pennsylvania's zone 7a have the same frost dates?
No — they do not all share a weather station, so frost dates vary by a week or more across the 50 locations listed (see the table above for each location's own dates).

Sources & method

Frost, freeze, growing-season, and growing-degree-day figures are NOAA NCEI U.S. Climate Normals 1991–2020, one reading per location's own nearest station (see the table above). The hardiness zone is the USDA Plant Hardiness Zone Map 2023, matched to each location's ZIP. Planting windows are computed by counting from the average last and first frost using per-crop offsets synthesized from U.S. Cooperative Extension guides — the full method and citations are on the methodology page.