State growing guide
Pennsylvania Planting Guide
USDA Zone 6a/6b · Last frost Apr 18 · First frost Oct 20 · 185 days
Zone-specific planting calendar, major city frost dates, top crops, and Duke's tips for growing food in Pennsylvania.
Frost Dates by City — Pennsylvania
Average frost dates for major Pennsylvania cities. Use these to calculate your indoor start dates and transplant windows.
| City | USDA Zone | Last Spring Frost | First Fall Frost | Tomato Transplant Window |
|---|---|---|---|---|
| Philadelphia | 7a | Apr 1 | Nov 1 | ~2 wks after (Apr 1) |
| Pittsburgh | 6a | Apr 20 | Oct 20 | ~2 wks after (Apr 20) |
| Allentown | 6b | Apr 10 | Oct 28 | ~2 wks after (Apr 10) |
| Harrisburg | 6b | Apr 10 | Oct 25 | ~2 wks after (Apr 10) |
| Erie | 5a | May 10 | Sep 30 | ~2 wks after (May 10) |
| Scranton | 5b | May 1 | Oct 12 | ~2 wks after (May 1) |
Average dates based on 30-year NOAA climate normals. Individual years may vary ±2 weeks. Use the Zone Lookup Tool for ZIP-specific dates.
Duke's Top Tips for Pennsylvania Gardeners
- Philadelphia (Zone 7a) can transplant tomatoes in late April
- Pittsburgh and Allentown transplant in late April to early May
- Pennsylvania Dutch country (Lancaster) has excellent garden soil — deep, well-drained loam
Common Challenges in Pennsylvania
- ⚠ Northern PA and Erie (Zone 5a–5b) have very cold winters and late springs
- ⚠ Powdery mildew on cucurbits is heavy in humid summers
Best Crops for Pennsylvania
Get exact dates for your ZIP code in Pennsylvania
City averages are a starting point. Your actual microclimate matters — enter your ZIP for precise frost dates.
Frequently Asked Questions — Pennsylvania Gardening
What zone is Pennsylvania?
Pennsylvania spans Zones 5a (Erie area, northern mountains) to 7a (Philadelphia). Pittsburgh is Zone 6a, Harrisburg and Allentown are Zone 6b, and Philadelphia is Zone 7a.
When to plant tomatoes in Philadelphia?
Philadelphia (Zone 7a) gardeners can transplant tomatoes in the last week of April or early May. Last frost is around April 1, but cold snaps can persist.