Upper Darby, PA frost dates
Last spring frostMar 30median date
First fall frostNov 17median date
Growing season232 daysfrost-free
Hardiness zone7bZone 7b
How Upper Darby compares
- In 8 years out of 10, the last spring frost in Upper Darby falls between March 15 and April 12, a 28-day window. The first fall frost falls between November 4 and December 4.
- The median last frost is 28 days earlier than the Pennsylvania median of Apr 27.
- Its 232-day growing season is among the longest of the 1,787 Pennsylvania places with a regular frost season.
- The last frost is 6 days earlier than the zone 7b median of Apr 5. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 7b chart.
- The weather station records an average of 62 nights a year at or below 32°F.
- Upper Darby shares its weather station with Havertown, PA, 4 km away, so the two have the same frost dates.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | March 15 |
| 50% (median) | March 30 |
| 10% (safe for tender plants) | April 12 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | November 4 |
| 50% (median) | November 17 |
| 90% (late) | December 4 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Planting calendar for Upper Darby, PA
Upper Darby, PA frost dates — last frost Mar 30, first frost Nov 17, zone 7b. whenisthelastfrost.com
Crop
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Start indoors: Jan 5 to Jan 19Transplant outside: Mar 2 to Mar 16
Start indoors: Jan 19 to Feb 2Transplant outside: Apr 13 to Apr 27
Start indoors: Jan 19 to Feb 2Transplant outside: Apr 13 to Apr 27
Start indoors: Feb 2 to Feb 16Transplant outside: Apr 6 to Apr 20
Start indoors: Feb 2 to Feb 16Transplant outside: Mar 9 to Mar 23Sow outdoors: Mar 2 to Apr 6Plant for fall: Sep 22 to Oct 20
Start indoors: Feb 2 to Feb 16Transplant outside: Mar 2 to Mar 16Sow outdoors: Mar 2 to Mar 16Plant for fall: Sep 8 to Sep 29
Start indoors: Feb 2 to Feb 16Transplant outside: Mar 16 to Mar 30Plant for fall: Aug 11 to Sep 1
Start indoors: Feb 2 to Feb 16Transplant outside: Mar 9 to Mar 23Plant for fall: Aug 11 to Sep 1
Start indoors: Feb 2 to Feb 16Transplant outside: Mar 16 to Mar 30Plant for fall: Aug 11 to Sep 1
Start indoors: Feb 16 to Mar 2Transplant outside: Apr 20 to May 4Sow outdoors: Apr 20 to May 4
Start indoors: Feb 16 to Mar 2Transplant outside: Apr 6 to Apr 20
Sow outdoors: Feb 16 to Mar 9Plant for fall: Aug 25 to Sep 15
Sow outdoors: Feb 16 to Mar 9Plant for fall: Sep 22 to Oct 13
Sow outdoors: Feb 23 to Apr 6Plant for fall: Oct 6 to Oct 27
Start indoors: Mar 2 to Mar 9Transplant outside: Apr 13 to Apr 20Sow outdoors: Apr 6 to Apr 20Plant for fall: Sep 1 to Sep 15
Start indoors: Mar 2 to Mar 9Sow outdoors: Apr 6 to Apr 20Plant for fall: Sep 8 to Sep 22
Start indoors: Mar 2 to Mar 9Sow outdoors: Apr 6 to Apr 20
Start indoors: Mar 2 to Mar 9Transplant outside: Apr 13 to Apr 27
Sow outdoors: Mar 9 to Apr 6Plant for fall: Aug 25 to Sep 8
Sow outdoors: Mar 9 to Apr 6Plant for fall: Sep 8 to Sep 22
Sow outdoors: Mar 9 to Mar 30
Sow outdoors: Mar 16 to Apr 13Plant for fall: Sep 8 to Sep 22
Sow outdoors: Mar 16 to Apr 6Plant for fall: Sep 22 to Oct 13
Sow outdoors: Apr 6 to Apr 27Plant for fall: Sep 1 to Sep 15
Sow outdoors: Apr 6 to Apr 20
Transplant outside: Apr 13 to May 4
Plant for fall: Nov 3 to Dec 8
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Upper Darby, PA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 5 – Jan 19 | Mar 2 – Mar 16 | — | — |
| Peppers | Jan 19 – Feb 2 | Apr 13 – Apr 27 | — | — |
| Eggplant | Jan 19 – Feb 2 | Apr 13 – Apr 27 | — | — |
| Tomatoes | Feb 2 – Feb 16 | Apr 6 – Apr 20 | — | — |
| Lettuce | Feb 2 – Feb 16 | Mar 9 – Mar 23 | Mar 2 – Apr 6 | Sep 22 – Oct 20 |
| Kale | Feb 2 – Feb 16 | Mar 2 – Mar 16 | Mar 2 – Mar 16 | Sep 8 – Sep 29 |
| Broccoli | Feb 2 – Feb 16 | Mar 16 – Mar 30 | — | Aug 11 – Sep 1 |
| Cabbage | Feb 2 – Feb 16 | Mar 9 – Mar 23 | — | Aug 11 – Sep 1 |
| Cauliflower | Feb 2 – Feb 16 | Mar 16 – Mar 30 | — | Aug 11 – Sep 1 |
| Okra | Feb 16 – Mar 2 | Apr 20 – May 4 | Apr 20 – May 4 | — |
| Basil | Feb 16 – Mar 2 | Apr 6 – Apr 20 | — | — |
| Peas | — | — | Feb 16 – Mar 9 | Aug 25 – Sep 15 |
| Spinach | — | — | Feb 16 – Mar 9 | Sep 22 – Oct 13 |
| Radishes | — | — | Feb 23 – Apr 6 | Oct 6 – Oct 27 |
| Cucumbers | Mar 2 – Mar 9 | Apr 13 – Apr 20 | Apr 6 – Apr 20 | Sep 1 – Sep 15 |
| Zucchini & Summer Squash | Mar 2 – Mar 9 | — | Apr 6 – Apr 20 | Sep 8 – Sep 22 |
| Winter Squash & Pumpkins | Mar 2 – Mar 9 | — | Apr 6 – Apr 20 | — |
| Melons & Watermelon | Mar 2 – Mar 9 | Apr 13 – Apr 27 | — | — |
| Carrots | — | — | Mar 9 – Apr 6 | Aug 25 – Sep 8 |
| Beets | — | — | Mar 9 – Apr 6 | Sep 8 – Sep 22 |
| Potatoes | — | — | Mar 9 – Mar 30 | — |
| Swiss Chard | — | — | Mar 16 – Apr 13 | Sep 8 – Sep 22 |
| Cilantro | — | — | Mar 16 – Apr 6 | Sep 22 – Oct 13 |
| Green Beans | — | — | Apr 6 – Apr 27 | Sep 1 – Sep 15 |
| Sweet Corn | — | — | Apr 6 – Apr 20 | — |
| Sweet Potatoes | — | Apr 13 – May 4 | — | — |
| Garlic | — | — | — | Nov 3 – Dec 8 |
Dates come from the median frost dates and common extension-service timing. Adjust for your soil temperature, microclimate and the varieties you grow.
About these dates
Based on 1991–2020 NOAA climate normals for the Phila Franklin Inst, PA weather station, 8 km away (elevation 59 ft (18 m)).
Frost dates near Upper Darby
- Lansdowne Mar 30 · Nov 17
- Drexel Hill Apr 2 · Nov 10
- Havertown Mar 30 · Nov 17
- Clifton Heights Apr 2 · Nov 10
- Darby Apr 2 · Nov 10
- Wynnewood Mar 30 · Nov 17
- Merion Station Mar 30 · Nov 17
- Ardmore Mar 30 · Nov 17
- Sharon Hill Apr 2 · Nov 10
- Glenolden Apr 2 · Nov 10
Frequently asked questions
When is the last frost in Upper Darby, PA?
The median last spring frost in Upper Darby, PA is March 30. There is still about a 10% chance of frost after April 12, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Upper Darby, PA?
The median first fall frost is November 17, with about a 10% chance of frost before November 4.
How long is the growing season in Upper Darby, PA?
About 232 days between the median last spring frost and first fall frost.
What planting zone is Upper Darby, PA?
Upper Darby, PA is in USDA hardiness zone 7b.