When to Plant in Philadelphia, PA: Planting Calendar & Frost Dates
Quick answer
In Philadelphia (ZIP 19103), the median last spring frost is Mar 30 and the first fall frost is Nov 17. Start tomato seeds indoors Feb 2 – Feb 16 and transplant them Apr 6 – Apr 13; sow peas Feb 16 – Mar 2; plant garlic Nov 3 – Dec 8.
For ZIP 19103 in Philadelphia, the nearest NOAA weather station with freeze records is Philadelphia Franklin Institute (NOAA name: Phila Franklin Inst, PA), 0.4 miles away. Its median last spring frost (32°F, NOAA 1991–2020) is Mar 30 and its median first fall frost is Nov 17, leaving about 232 frost-free days. ZIP 19103 is in USDA hardiness zone 7b. The last frost here comes 12 days earlier than the zone 7 median (Apr 11), and the season is 32 days longer than the zone’s typical 200 days. Across Pennsylvania’s 1,833 ZIP codes with frost dates, the median last frost is Apr 27, so Philadelphia’s comes 28 days earlier than that.
Station and dates: NOAA NCEI U.S. Climate Normals 1991–2020, 32°F at 50% probability, for the station nearest the center of ZIP 19103. Zone: 2023 USDA Plant Hardiness Zone Map (PRISM data by ZIP code).
Next 30 days in Philadelphia
See what to plant this month in the planner for ZIP 19103.
Key planting dates for Philadelphia
| Key date | When in Philadelphia | How it is counted |
|---|---|---|
| Sow peas | Feb 16 – Mar 2 | 4–6 weeks before last frost (Mar 30) |
| Start tomatoes indoors | Feb 2 – Feb 16 | 6–8 weeks before last frost (Mar 30) |
| Transplant tomatoes | Apr 6 – Apr 13 | 1–2 weeks after last frost (Mar 30) |
| Sow beans and squash | Apr 6 – Apr 13 | 1–2 weeks after last frost (Mar 30) |
| Sow fall lettuce | Sep 22 – Oct 6 | 6–8 weeks before first fall frost (Nov 17) |
| Plant garlic | Nov 3 – Dec 8 | 2 weeks before to 3 weeks after first fall frost, while the soil is still workable (SDSU, Illinois, Virginia Tech) (Nov 17) |
| Plant tulip bulbs | Nov 3 – Dec 15 | 2 weeks before to 4 weeks after first fall frost (our approximation of when soil falls below 60°F; Rutgers) (Nov 17) |
Philadelphia vegetable and flower planting calendar
Every date range below is counted from Philadelphia’s median frost dates (Mar 30 and Nov 17) with the same rules as our planner, and rows run in calendar order. In about half of years a frost still comes after the spring date.
| Plant | Task | Dates (and how they are counted) | Expected harvest (estimate) |
|---|---|---|---|
| Broccoli | Start indoors | Jan 19 – Feb 28–10 weeks before last frost (avg. Mar 30) | — |
| Cabbage | Start indoors | Jan 19 – Feb 28–10 weeks before last frost (avg. Mar 30) | — |
| Kale | Start indoors | Jan 19 – Feb 28–10 weeks before last frost (avg. Mar 30) | — |
| Tomatoes | Start indoors | Feb 2 – Feb 166–8 weeks before last frost (avg. Mar 30) | — |
| Peppers | Start indoors | Feb 2 – Feb 166–8 weeks before last frost (avg. Mar 30) | — |
| Eggplant | Start indoors | Feb 2 – Feb 166–8 weeks before last frost (avg. Mar 30) | — |
| Peas | Direct sow | Feb 16 – Mar 24–6 weeks before last frost (avg. Mar 30) | Apr 17 – May 2160–80 days from seeding |
| Spinach | Direct sow | Feb 16 – Mar 24–6 weeks before last frost (avg. Mar 30) | Apr 2 – May 145–60 days from seeding |
| Basil | Start indoors | Feb 16 – Mar 24–6 weeks before last frost (avg. Mar 30) | — |
| Radishes | Direct sow | Feb 23 – Mar 162–5 weeks before last frost (avg. Mar 30) | Mar 15 – Apr 1520–30 days from seeding |
| Lettuce | Direct sow | Mar 2 – Mar 162–4 weeks before last frost (avg. Mar 30) | May 1 – Jun 460–80 days from seeding |
| Onions (sets/transplants) | Plant sets/transplants | Mar 2 – Mar 162–4 weeks before last frost (avg. Mar 30) | May 26 – Jul 1485–120 days from planting |
| Broccoli | Transplant | Mar 2 – Mar 162–4 weeks before last frost (avg. Mar 30) | Apr 21 – May 2550–70 days from transplanting |
| Cabbage | Transplant | Mar 2 – Mar 162–4 weeks before last frost (avg. Mar 30) | May 11 – Jun 1470–90 days from transplanting |
| Kale | Transplant | Mar 2 – Mar 162–4 weeks before last frost (avg. Mar 30) | — |
| Marigolds | Start indoors | Mar 9 – Mar 300–3 weeks before last frost (3–4 weeks before setting out; Univ. of Idaho) (avg. Mar 30) | — |
| Zinnias | Start indoors | Mar 9 – Mar 300–3 weeks before last frost (3–4 weeks before setting out; Univ. of Idaho) (avg. Mar 30) | — |
| Potatoes | Plant seed potatoes | Mar 16 – Mar 231–2 weeks before last frost (avg. Mar 30) | Jun 9 – Jul 1185–110 days from planting |
| Marigolds | Direct sow / transplant | Mar 30 – Apr 13from the last frost to 2 weeks after (Univ. of Idaho) (avg. Mar 30) | — |
| Zinnias | Direct sow / transplant | Mar 30 – Apr 13from the last frost to 2 weeks after (Univ. of Idaho) (avg. Mar 30) | — |
| Tomatoes | Transplant | Apr 6 – Apr 131–2 weeks after last frost (avg. Mar 30) | Jun 15 – Jul 1270–90 days from transplanting |
| Beans (bush & pole) | Direct sow | Apr 6 – Apr 131–2 weeks after last frost (avg. Mar 30) | May 21 – Jun 2245–70 days from seeding |
| Sweet corn | Direct sow | Apr 6 – Apr 131–2 weeks after last frost (avg. Mar 30) | Jun 10 – Jul 1265–90 days from seeding |
| Cucumbers | Direct sow | Apr 6 – Apr 131–2 weeks after last frost (avg. Mar 30) | May 16 – Jun 1740–65 days from seeding |
| Squash | Direct sow | Apr 6 – Apr 131–2 weeks after last frost (avg. Mar 30) | May 16 – Jun 240–50 days from seeding |
| Pumpkins | Direct sow | Apr 6 – Apr 201–3 weeks after last frost (avg. Mar 30) | Jun 25 – Jul 2980–100 days from seeding |
| Basil | Transplant | Apr 6 – Apr 131–2 weeks after last frost (avg. Mar 30) | May 18 – May 2542 days from transplanting |
| Peppers | Transplant | Apr 13 – Apr 202–3 weeks after last frost (avg. Mar 30) | Jun 17 – Jul 465–75 days from transplanting |
| Eggplant | Transplant | Apr 13 – Apr 202–3 weeks after last frost (avg. Mar 30) | Jun 22 – Jul 1970–90 days from transplanting |
| Broccoli | Fall transplant | Aug 25 – Sep 810–12 weeks before first fall frost (avg. Nov 17) | Oct 14 – Nov 1750–70 days from transplanting |
| Cabbage | Fall transplant | Aug 25 – Sep 810–12 weeks before first fall frost (avg. Nov 17) | Nov 3 – Dec 770–90 days from transplanting |
| Kale | Fall sow | Sep 8 – Sep 228–10 weeks before first fall frost (avg. Nov 17) | Oct 28 – Dec 150–70 days from seeding |
| Lettuce | Fall sow | Sep 22 – Oct 66–8 weeks before first fall frost (avg. Nov 17) | Nov 21 – Dec 2560–80 days from seeding |
| Spinach | Fall sow | Sep 29 – Oct 204–7 weeks before first fall frost (Virginia Tech) (avg. Nov 17) | Nov 13 – Dec 1945–60 days from seeding |
| Radishes | Fall sow | Oct 6 – Oct 204–6 weeks before first fall frost (avg. Nov 17) | Oct 26 – Nov 1920–30 days from seeding |
| Daffodils | Fall plant bulbs | Oct 20 – Dec 14 weeks before to 2 weeks after first fall frost (our approximation of when soil falls below 60°F; Rutgers) (avg. Nov 17) | — |
| Tulips | Fall plant bulbs | Nov 3 – Dec 152 weeks before to 4 weeks after first fall frost (our approximation of when soil falls below 60°F; Rutgers) (avg. Nov 17) | — |
| Garlic | Fall plant cloves | Nov 3 – Dec 82 weeks before to 3 weeks after first fall frost, while the soil is still workable (SDSU, Illinois, Virginia Tech) (avg. Nov 17) | Jul 11 – Sep 4 (next year)250–270 days from planting |
How we count planting dates: the weeks before or after frost for each crop come from university extension planting guides: UNH Extension, When to Plant Your Vegetable Garden; Rutgers FS787, Starting Vegetable Seeds Indoors; Virginia Tech 426-331, Home Garden Vegetable Planting Guide; University of Maryland Extension, Vegetable Planting Calendar; and University of Idaho CIS 1209 (marigolds and zinnias). Bulb windows approximate Rutgers’ rule to plant when soil falls below 60°F (FS1220), and garlic follows SDSU, Illinois and Virginia Tech. Temperature notes: UMD (potatoes), UMN (sweet corn), UC ANR (peppers, hardening off), UMN (eggplant), Colorado State (tomatoes) and SDSU (hardening off).
Harvest estimates add days to harvest from these sources to each planting window, and stop at the first fall frost for frost-tender crops: UF/IFAS Extension, Florida Vegetable Gardening Guide (SP103/VH021), Table 1, “Days to Harvest”; University of Maryland Extension, Growing Onions in a Home Garden; University of Maryland Extension, Growing Garlic in a Home Garden; University of Maryland Extension, Growing Basil in a Home Garden.
Frost dates across Philadelphia’s ZIP codes
Across Philadelphia’s 49 ZIP codes, the median last spring frost ranges from Mar 30 to Apr 15 and the median first fall frost from Oct 31 to Nov 17, depending on which of 5 NOAA stations is nearest. This page uses ZIP 19103, which is in the group most Philadelphia ZIP codes share.
| Nearest NOAA station | Last spring frost | First fall frost | Philadelphia ZIP codes |
|---|---|---|---|
| Philadelphia Franklin Institute (NOAA name: Phila Franklin Inst, PA) | Mar 30 | Nov 17 | 33: 19102, 19103, 19104, 19106, 19107, 19108, 19109, 19119, 19120, 19121, 19122, 19123, 19125, 19127, 19128, 19129, 19130, 19131, 19132, 19133, 19134, 19138, 19139, 19140, 19141, 19143, 19144, 19145, 19146, 19147, 19148, 19150, 19151 |
| Philadelphia Northeast Airport (NOAA name: Philadelphia Ne Airport, PA) | Apr 4 | Nov 7 | 9: 19111, 19114, 19115, 19116, 19126, 19136, 19149, 19152, 19154 |
| Pennsauken 1N | Apr 15 | Oct 31 | 3: 19124, 19135, 19137 |
| Philadelphia International Airport (NOAA name: Philadelphia Intl Airport, PA) | Apr 2 | Nov 10 | 3: 19112, 19142, 19153 |
| Norristown | Apr 8 | Oct 31 | 1: 19118 |
Which ZIP codes count as Philadelphia: the 49 ZIP Code Tabulation Areas (2020 ZCTAs) with at least half of their land area inside Philadelphia city limits, from the U.S. Census Bureau, 2020 ZCTA to Place Relationship File. ZCTAs are the Census Bureau’s approximations of USPS ZIP Code areas, so this list may not match every USPS ZIP code. Each ZIP code’s dates are the ones our planner shows for it.
How Philadelphia compares
| Area | Median last spring frost | Median first fall frost | Frost-free days |
|---|---|---|---|
| Philadelphia (ZIP 19103) | Mar 30 | Nov 17 | 232 |
| Pennsylvania (median of 1,833 ZIP codes) | Apr 27 | Oct 21 | 177 |
| USDA zone 7 (median of 7,068 ZIP codes) | Apr 11 | Oct 28 | 200 |
How this table is built: each ZIP code is matched to its nearest NOAA 1991–2020 freeze-data station (within 60 miles); state and zone rows are medians across those ZIP codes. Zones are the 2023 USDA zones by ZIP code (PRISM).
More for Philadelphia gardeners
- Your own ZIP: open the planner for ZIP 19103 and change the ZIP to yours for its own station and dates.
- Pennsylvania: When to plant in Pennsylvania, with frost dates across the state.
- USDA zone 7b: our zone 7 planting guide.
- Also in Pennsylvania: Pittsburgh
- Frost tonight? How to protect plants from frost.
Wilmington Baltimore Pittsburgh Boston Chicago Minneapolis Denver Dallas Richmond Atlanta Seattle Phoenix Los Angeles Miami All cities
Frequently asked questions
When is the last frost in Philadelphia?
For ZIP 19103 in Philadelphia, the nearest NOAA 1991–2020 normals station (Philadelphia Franklin Institute, 0.4 miles away) has a median last spring frost (32°F) of Mar 30. Across Philadelphia’s 49 ZIP codes it ranges from Mar 30 to Apr 15. In about half of years a frost still comes after that date, so tender plants are safer 1–2 weeks later.
When should I plant tomatoes in Philadelphia?
Start tomato seeds indoors Feb 2 – Feb 16 (6–8 weeks before the last frost) and transplant them outdoors Apr 6 – Apr 13 (1–2 weeks after it), once nights stay above about 52°F (Colorado State).
What is the first fall frost date in Philadelphia?
The median first fall frost (32°F) for ZIP 19103 is Nov 17, about 232 days after the last spring frost. Across Philadelphia’s ZIP codes it ranges from Oct 31 to Nov 17. Sow fall lettuce Sep 22 – Oct 6 and plant garlic Nov 3 – Dec 8.
What USDA zone is Philadelphia in?
ZIP 19103 in Philadelphia is in USDA hardiness zone 7b on the 2023 USDA map (by ZIP code, via PRISM). Hardiness zones describe winter low temperatures, not frost dates.
Sources
- NOAA National Centers for Environmental Information: U.S. Climate Normals 1991–2020
- USDA Agricultural Research Service, Plant Hardiness Zone Map: 2023 USDA Plant Hardiness Zone Map
- UNH Extension: When to Plant Your Vegetable Garden
- Rutgers NJAES Cooperative Extension: Rutgers FS787, Starting Vegetable Seeds Indoors; FS1220: Spring Flowering Bulbs (Rutgers NJAES)
- Virginia Cooperative Extension (Virginia Tech): Virginia Cooperative Extension 426-331, Virginia’s Home Garden Vegetable Planting Guide
- University of Maryland Extension: Vegetable Planting Calendar; Growing Potatoes in a Home Garden; Growing Onions in a Home Garden; Growing Garlic in a Home Garden; Growing Basil in a Home Garden
- University of Idaho Extension: CIS 1209
- South Dakota State University Extension: Planting Garlic; Harden Your Transplants Prior To Planting Your Garden
- University of Illinois Extension: Ready, Set, Garlic!
- University of Minnesota Extension: Growing sweet corn in home gardens; Growing eggplant in home gardens
- University of California Agriculture and Natural Resources (UC ANR): Growing Peppers
- Colorado State University Extension: Growing tomatoes
- UF/IFAS Extension: Florida Vegetable Gardening Guide (SP103/VH021), Table 1, “Days to Harvest”
- U.S. Census Bureau: 2020 ZCTA to Place Relationship File