When to plant basil in Pennsylvania

Basil
Plant out in Philadelphia
Apr 6–Apr 20

Across Pennsylvania the window opens between April 6 and May 7. Find your city below; the dates follow each town's own average last frost.

Start indoors, Philadelphia
Feb 16–Mar 2
Plant out, Philadelphia
Apr 6–Apr 20
Sow outdoors, Philadelphia
Apr 6–Apr 20
Last sowing for a harvest
Aug 20
Last frost, Philadelphia
Mar 30

Start seeds indoors 4–6 weeks before the last frost; plant out 1–3 weeks after the last frost; sow outdoors 1–3 weeks after the last frost. Basil blackens below 50°F. Wait a week or two after the last frost.

Basil planting dates by city

Start indoorsPlant outSow outdoorsFall plantingAverage last and first frost
JanFebMarAprMayJunJulAugSepOctNovDec
PhiladelphiaApr 6–Apr 20
PittsburghApr 25–May 9
AllentownApr 27–May 11
ReadingApr 21–May 5
ErieMay 3–May 17
BethlehemApr 27–May 11
ScrantonApr 30–May 14
LancasterApr 26–May 10
LevittownApr 28–May 12
HarrisburgApr 22–May 6
YorkMay 3–May 17
Wilkes-BarreApr 30–May 14
AltoonaMay 2–May 16
State CollegeApr 27–May 11
Penn HillsApr 23–May 7
NorristownApr 15–Apr 29
ChesterApr 6–Apr 20
Mount LebanonApr 25–May 9
Bethel ParkApr 25–May 9
EastonApr 25–May 9
HazletonMay 7–May 21
Drexel HillApr 9–Apr 23
MonroevilleApr 29–May 13
WilliamsportMay 2–May 16
LebanonApr 27–May 11
PlumApr 23–May 7
King of PrussiaApr 15–Apr 29
ChambersburgApr 25–May 9
PottstownApr 27–May 11
CarlisleApr 30–May 14
All 35 cities
CityStart indoorsPlant outSow outdoorsLast frost
PhiladelphiaFeb 16 to Mar 2Apr 6 to Apr 20Apr 6 to Apr 20Mar 30
PittsburghMar 7 to Mar 21Apr 25 to May 9Apr 25 to May 9Apr 18
AllentownMar 9 to Mar 23Apr 27 to May 11Apr 27 to May 11Apr 20
ReadingMar 3 to Mar 17Apr 21 to May 5Apr 21 to May 5Apr 14
ErieMar 15 to Mar 29May 3 to May 17May 3 to May 17Apr 26
BethlehemMar 9 to Mar 23Apr 27 to May 11Apr 27 to May 11Apr 20
ScrantonMar 12 to Mar 26Apr 30 to May 14Apr 30 to May 14Apr 23
LancasterMar 8 to Mar 22Apr 26 to May 10Apr 26 to May 10Apr 19
LevittownMar 10 to Mar 24Apr 28 to May 12Apr 28 to May 12Apr 21
HarrisburgMar 4 to Mar 18Apr 22 to May 6Apr 22 to May 6Apr 15
YorkMar 15 to Mar 29May 3 to May 17May 3 to May 17Apr 26
Wilkes-BarreMar 12 to Mar 26Apr 30 to May 14Apr 30 to May 14Apr 23
AltoonaMar 14 to Mar 28May 2 to May 16May 2 to May 16Apr 25
State CollegeMar 9 to Mar 23Apr 27 to May 11Apr 27 to May 11Apr 20
Penn HillsMar 5 to Mar 19Apr 23 to May 7Apr 23 to May 7Apr 16
NorristownFeb 25 to Mar 11Apr 15 to Apr 29Apr 15 to Apr 29Apr 8
ChesterFeb 16 to Mar 2Apr 6 to Apr 20Apr 6 to Apr 20Mar 30
Mount LebanonMar 7 to Mar 21Apr 25 to May 9Apr 25 to May 9Apr 18
Bethel ParkMar 7 to Mar 21Apr 25 to May 9Apr 25 to May 9Apr 18
EastonMar 7 to Mar 21Apr 25 to May 9Apr 25 to May 9Apr 18
HazletonMar 19 to Apr 2May 7 to May 21May 7 to May 21Apr 30
Drexel HillFeb 19 to Mar 5Apr 9 to Apr 23Apr 9 to Apr 23Apr 2
MonroevilleMar 11 to Mar 25Apr 29 to May 13Apr 29 to May 13Apr 22
WilliamsportMar 14 to Mar 28May 2 to May 16May 2 to May 16Apr 25
LebanonMar 9 to Mar 23Apr 27 to May 11Apr 27 to May 11Apr 20
PlumMar 5 to Mar 19Apr 23 to May 7Apr 23 to May 7Apr 16
King of PrussiaFeb 25 to Mar 11Apr 15 to Apr 29Apr 15 to Apr 29Apr 8
ChambersburgMar 7 to Mar 21Apr 25 to May 9Apr 25 to May 9Apr 18
PottstownMar 9 to Mar 23Apr 27 to May 11Apr 27 to May 11Apr 20
CarlisleMar 12 to Mar 26Apr 30 to May 14Apr 30 to May 14Apr 23
Allison ParkMar 5 to Mar 19Apr 23 to May 7Apr 23 to May 7Apr 16
New CastleMar 19 to Apr 2May 7 to May 21May 7 to May 21Apr 30
MurrysvilleMar 11 to Mar 25Apr 29 to May 13Apr 29 to May 13Apr 22
BaldwinMar 7 to Mar 21Apr 25 to May 9Apr 25 to May 9Apr 18
PhoenixvilleMar 7 to Mar 21Apr 25 to May 9Apr 25 to May 9Apr 18

Questions

When should I plant basil in Pennsylvania?

In Philadelphia, plant out from April 6 to April 20. Across Pennsylvania the window opens between April 6 and May 7, depending on the local last frost.

How is this date worked out?

Start seeds indoors 4–6 weeks before the last frost; plant out 1–3 weeks after the last frost; sow outdoors 1–3 weeks after the last frost. Frost dates are NOAA 1991–2020 averages for the weather station nearest each city.

More for Pennsylvania

Basil in other states

Frost dates for every city in Pennsylvania