When to plant watermelon in Pennsylvania
Pennsylvania spans USDA zones 5b–7b, so the right time to plant watermelon shifts by weeks across the state. The window to transplant seedlings outdoors runs from about April 6 in Philadelphia to May 22 in Hermitage — below are local dates for 86 cities, each computed from its own frost dates.
| City | Zone | Last frost | First frost | Transplant out |
|---|---|---|---|---|
| Philadelphia | 7b | March 30 | November 17 | April 6 – April 13 |
| Pittsburgh | 6b | April 18 | October 28 | April 25 – May 2 |
| Allentown | 7a | April 20 | October 24 | April 27 – May 4 |
| Reading | 7a | April 14 | October 29 | April 21 – April 28 |
| Erie | 7a | April 26 | November 4 | May 3 – May 10 |
| Bethlehem | 7a | April 20 | October 24 | April 27 – May 4 |
| Scranton | 6b | April 23 | October 20 | April 30 – May 7 |
| Lancaster | 7a | April 19 | October 24 | April 26 – May 3 |
Watermelon in Pennsylvania: FAQ
When can I plant watermelon in Pennsylvania?
Across Pennsylvania, the time to transplant watermelon spans roughly April 6 in Philadelphia to May 22 in Hermitage, each following that city's local frost dates.
Does the watermelon planting date vary across Pennsylvania?
Yes. Pennsylvania publishes 86 cities with their own frost dates, so the right watermelon planting window shifts by weeks between the warmest and coldest parts of the state — use your city's page for the exact dates.
How long does watermelon take to grow in Pennsylvania?
Watermelon takes about 75–95 days to reach harvest once planted — check that this fits inside your city's frost-free season on its place page.
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