When to plant Watermelon in Pennsylvania

In spring, from Apr 10 – May 15 in Chester to June 1 – 15 in St. Marys.

In fall, from May 15 – June 1 in Hermitage to July 15 – 30 in Yeadon.

USDA's earliest safe spring and latest safe fall planting dates, matched to each place's average frost dates.

Watermelon planting dates by place in Pennsylvania
PlaceSpringFall
AllentownMay 1 – June 15June 15 – July 20
AltoonaMay 1 – June 15June 15 – July 20
BaldwinMay 1 – June 15July 1 – 15
BerwickMay 15 – June 15June 1 – 15
Bethel ParkMay 1 – June 15July 1 – 15
BethlehemMay 1 – June 15June 15 – July 20
BloomsburgMay 15 – June 15June 15 – July 20
ButlerJune 1 – 15June 1 – 15
CarlisleMay 1 – June 15June 15 – July 20
ChambersburgMay 1 – June 15June 15 – July 20
ChesterApr 10 – May 15Not listed
CoatesvilleMay 1 – June 15June 15 – July 20
ColumbiaMay 15 – June 15June 1 – 15
DarbyApr 10 – May 15July 15 – 30
DunmoreMay 1 – June 15June 15 – July 20
EastonMay 1 – June 15June 15 – July 20
ElizabethtownApr 20 – June 1July 1 – 15
EmmausMay 1 – June 15June 15 – July 20
EphrataMay 1 – June 15June 15 – July 20
ErieMay 15 – June 15July 1 – 15
Franklin ParkMay 1 – June 15July 1 – 15
GreensburgMay 15 – June 15June 1 – 15
HanoverMay 1 – June 15June 15 – July 20
HarrisburgApr 20 – June 1June 15 – July 20
HazletonMay 15 – June 15June 15 – July 20
HermitageJune 1 – 15May 15 – June 1
IndianaJune 1 – 15June 1 – 15
Jefferson HillsMay 1 – June 15July 1 – 15
JohnstownMay 15 – June 15June 15 – July 20
KingstonMay 1 – June 15June 15 – July 20
LancasterMay 1 – June 15June 15 – July 20
LansdaleApr 20 – June 1July 1 – 15
LansdowneApr 10 – May 15July 15 – 30
LebanonMay 1 – June 15June 15 – July 20
Lower BurrellMay 1 – June 15July 1 – 15
McKeesportMay 15 – June 15June 15 – July 20
MeadvilleMay 15 – June 15June 15 – July 20
MechanicsburgApr 20 – June 1July 1 – 15
MonroevilleMay 1 – June 15June 15 – July 20
MunhallApr 20 – June 1July 15 – 30
MurrysvilleMay 1 – June 15June 15 – July 20
NanticokeJune 1 – 15June 1 – 15
New CastleMay 15 – June 15June 15 – July 20
New KensingtonMay 1 – June 15July 1 – 15
NorristownApr 20 – June 1July 1 – 15
NorthamptonMay 1 – June 15June 15 – July 20
PhiladelphiaApr 10 – May 15Not listed
PhoenixvilleMay 1 – June 15July 1 – 15
PittsburghMay 1 – June 15July 1 – 15
PlumMay 1 – June 15July 1 – 15
PottstownMay 1 – June 15June 15 – July 20
PottsvilleMay 15 – June 15June 15 – July 20
ReadingApr 20 – June 1July 1 – 15
ScrantonMay 1 – June 15June 15 – July 20
SharonMay 15 – June 15June 15 – July 20
St. MarysJune 1 – 15June 1 – 15
State CollegeMay 1 – June 15July 1 – 15
WashingtonMay 1 – June 15June 15 – July 20
WaynesboroMay 1 – June 15June 15 – July 20
West ChesterMay 15 – June 15June 15 – July 20
West MifflinMay 1 – June 15July 1 – 15
WhitehallMay 1 – June 15July 1 – 15
Wilkes-BarreMay 1 – June 15June 15 – July 20
WilkinsburgApr 20 – June 1July 15 – 30
WilliamsportMay 1 – June 15June 15 – July 20
WyomissingApr 20 – June 1July 1 – 15
YeadonApr 10 – May 15July 15 – 30
YorkMay 15 – June 15June 15 – July 20

Planting dates: USDA Home and Garden Bulletin No. 9 (1967), tables 4 and 5. Frost dates: NOAA U.S. Climate Normals 1991–2020. “—” means the place's frost date is outside the table. The full USDA table for watermelon.