USDA hardiness zone lookup
Philadelphia, PA — USDA Zone 7b
Philadelphia, Pennsylvania · 208-day growing season
Frost dates and growing season in Philadelphia
| USDA hardiness zone | Zone 7b |
|---|---|
| Average last spring frost | April 11 |
| Average first fall frost | November 5 |
| Growing season length | ~208 days |
| Temperature range (F) | 0 to 10°F |
| Temperature range (C) | -18 to -12°C |
All of Philadelphia's mapped ZIP codes fall in the same hardiness band, Zone 7b.
These are 50%-probability averages modeled from Philadelphia's USDA hardiness zone and regional climate normals — not a single-station reading. In a typical year the last spring frost will have passed by April 11, but a colder-than-average year can run 1-2 weeks later. Plant tender crops (tomatoes, peppers, basil) once both soil and night temperatures are consistently warm — a thermometer beats the calendar.
Growing season in Philadelphia
Philadelphia, Pennsylvania sits in USDA Zone 7b, with roughly 208 frost-free days between an average last spring frost around April 11 and a first fall frost around November 5. That is a long season — succession-sow through summer and run a full fall crop; heat-sensitive greens still need spring/autumn timing. Philadelphia lies near 40.0°N; higher-latitude gardens get longer midsummer days but a tighter shoulder season at this zone. As a large metro, the built-up core typically runs up to half a zone warmer than outlying suburbs through the urban heat-island effect — sheltered city gardens often push tender crops a little earlier than the average suggests.
What grows in Philadelphia
Philadelphia falls in USDA Zone 7b, so the same hardiness constraints apply as the full Zone 7 guide. Vegetables, herbs, and fruit trees rated to Zone 7b (or hardier) will overwinter here in a typical year.
- Tomatoes, peppers, eggplant
- Okra
- Sweet potatoes
- Squash, melons
- Beans (lima + pole)
- Figs
- Pomegranates (in protected spots)
- Apples, peaches, plums, pears
- Blueberries (rabbiteye + highbush)
- Asparagus, rhubarb
What to plant in Philadelphia this week
Philadelphia is in high summer — most spring plantings are in. Keep an eye on watering and start planning your fall crop. Cool-season seedlings (broccoli, cabbage, lettuce) can be started indoors for a fall transplant.
- When to plant tomatoes in zone 7
- When to plant peppers in zone 7
- When to plant bush beans in zone 7
- When to plant cucumbers in zone 7
- When to plant basil in zone 7
Full planting calendar for Philadelphia
Crop-by-crop sowing, transplant, and harvest dates calibrated to zone 7 averages:
- When to plant tomatoes in zone 7
- When to plant peppers in zone 7
- When to plant basil in zone 7
- When to plant garlic in zone 7
- When to plant lettuce in zone 7
- When to plant bush beans in zone 7
- When to plant cucumbers in zone 7
- When to plant summer squash in zone 7
- When to plant peas in zone 7
- When to plant carrots in zone 7
ZIP codes in Philadelphia
Drill down to the precise frost window and planting calendar for a specific ZIP in Philadelphia:
- 19102 — Philadelphia (Zone 7b)
- 19103 — Philadelphia (Center City) (Zone 7b)
- 19104 — Philadelphia (University City) (Zone 7b)
- 19111 — Philadelphia (Fox Chase) (Zone 7a)
- 19120 — Philadelphia (Olney) (Zone 7b)
- 19124 — Philadelphia (Frankford) (Zone 7b)
- 19143 — Philadelphia (Southwest) (Zone 7b)
Local microclimate notes
Zone tables give you the average — but Philadelphiagardens vary. South-facing walls and paved areas can run a full half-zone warmer than the published rating. Low-lying spots, frost pockets, and shaded north sides can run colder. If you've gardened here a few seasons, your own frost record — the last time you actually got frost damage — beats any national average.
Source and methodology
Hardiness zone from the USDA Plant Hardiness Zone Map (2023 revision). Frost-date and growing-season figures are modeled from Philadelphia's USDA hardiness zone and regional NOAA 1991-2020 climate normals — zone-level estimates, not a per-station record, so treat them as planning guidance and confirm against your own local frost history. Crop recommendations draw on US Cooperative Extension references, curated by the Growli editorial team. Last reviewed June 2026.
Other cities in Pennsylvania
- Allentown, PA — USDA Zone 6b
- Altoona, PA — USDA Zone 6a
- Erie, PA — USDA Zone 6b
- Harrisburg, PA — USDA Zone 7a
- Lancaster, PA — USDA Zone 7a
- Pittsburgh, PA — USDA Zone 6b
- Reading, PA — USDA Zone 7a
- Scranton, PA — USDA Zone 6a
- State College, PA — USDA Zone 6a
- Wilkes-Barre, PA — USDA Zone 6a
- York, PA — USDA Zone 7a
- All of Pennsylvania by zone