Frost dates for 17113 — Harrisburg, PA
Last spring frostApr 9median date
First fall frostNov 1median date
Growing season206 daysfrost-free
Hardiness zone7aZone 7a
How Harrisburg compares
- In 8 years out of 10, the last spring frost in Harrisburg falls between March 27 and April 25, a 29-day window. The first fall frost falls between October 16 and November 15.
- The median last frost is 18 days earlier than the Pennsylvania median of Apr 27.
- Its 206-day growing season is longer than 92% of the 1,787 Pennsylvania places with a regular frost season (state median 175 days).
- The last frost is 7 days earlier than the zone 7a median of Apr 16. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 7a chart.
- The weather station records an average of 102 nights a year at or below 32°F.
- Compared with Lancaster, PA, 50 km away, the last frost here is 10 days earlier than there and the growing season is 18 days longer.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | March 27 |
| 50% (median) | April 9 |
| 10% (safe for tender plants) | April 25 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 16 |
| 50% (median) | November 1 |
| 90% (late) | November 15 |
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 Harrisburg, PA
Frost dates for 17113 — Harrisburg, PA — last frost Apr 9, first frost Nov 1, zone 7a. whenisthelastfrost.com
Crop
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Start indoors: Jan 15 to Jan 29Transplant outside: Mar 12 to Mar 26
Start indoors: Jan 29 to Feb 12Transplant outside: Apr 23 to May 7
Start indoors: Jan 29 to Feb 12Transplant outside: Apr 23 to May 7
Start indoors: Feb 12 to Feb 26Transplant outside: Apr 16 to Apr 30
Start indoors: Feb 12 to Feb 26Transplant outside: Mar 19 to Apr 2Sow outdoors: Mar 12 to Apr 16Plant for fall: Sep 6 to Oct 4
Start indoors: Feb 12 to Feb 26Transplant outside: Mar 12 to Mar 26Sow outdoors: Mar 12 to Mar 26Plant for fall: Aug 23 to Sep 13
Start indoors: Feb 12 to Feb 26Transplant outside: Mar 26 to Apr 9Plant for fall: Jul 26 to Aug 16
Start indoors: Feb 12 to Feb 26Transplant outside: Mar 19 to Apr 2Plant for fall: Jul 26 to Aug 16
Start indoors: Feb 12 to Feb 26Transplant outside: Mar 26 to Apr 9Plant for fall: Jul 26 to Aug 16
Start indoors: Feb 26 to Mar 12Transplant outside: Apr 30 to May 14Sow outdoors: Apr 30 to May 14
Start indoors: Feb 26 to Mar 12Transplant outside: Apr 16 to Apr 30
Sow outdoors: Feb 26 to Mar 19Plant for fall: Aug 9 to Aug 30
Sow outdoors: Feb 26 to Mar 19Plant for fall: Sep 6 to Sep 27
Sow outdoors: Mar 5 to Apr 16Plant for fall: Sep 20 to Oct 11
Start indoors: Mar 12 to Mar 19Transplant outside: Apr 23 to Apr 30Sow outdoors: Apr 16 to Apr 30Plant for fall: Aug 16 to Aug 30
Start indoors: Mar 12 to Mar 19Sow outdoors: Apr 16 to Apr 30Plant for fall: Aug 23 to Sep 6
Start indoors: Mar 12 to Mar 19Sow outdoors: Apr 16 to Apr 30
Start indoors: Mar 12 to Mar 19Transplant outside: Apr 23 to May 7
Sow outdoors: Mar 19 to Apr 16Plant for fall: Aug 9 to Aug 23
Sow outdoors: Mar 19 to Apr 16Plant for fall: Aug 23 to Sep 6
Sow outdoors: Mar 19 to Apr 9
Sow outdoors: Mar 26 to Apr 23Plant for fall: Aug 23 to Sep 6
Sow outdoors: Mar 26 to Apr 16Plant for fall: Sep 6 to Sep 27
Sow outdoors: Apr 16 to May 7Plant for fall: Aug 16 to Aug 30
Sow outdoors: Apr 16 to Apr 30
Transplant outside: Apr 23 to May 14
Plant for fall: Oct 18 to Nov 22
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Harrisburg, PA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 15 – Jan 29 | Mar 12 – Mar 26 | — | — |
| Peppers | Jan 29 – Feb 12 | Apr 23 – May 7 | — | — |
| Eggplant | Jan 29 – Feb 12 | Apr 23 – May 7 | — | — |
| Tomatoes | Feb 12 – Feb 26 | Apr 16 – Apr 30 | — | — |
| Lettuce | Feb 12 – Feb 26 | Mar 19 – Apr 2 | Mar 12 – Apr 16 | Sep 6 – Oct 4 |
| Kale | Feb 12 – Feb 26 | Mar 12 – Mar 26 | Mar 12 – Mar 26 | Aug 23 – Sep 13 |
| Broccoli | Feb 12 – Feb 26 | Mar 26 – Apr 9 | — | Jul 26 – Aug 16 |
| Cabbage | Feb 12 – Feb 26 | Mar 19 – Apr 2 | — | Jul 26 – Aug 16 |
| Cauliflower | Feb 12 – Feb 26 | Mar 26 – Apr 9 | — | Jul 26 – Aug 16 |
| Okra | Feb 26 – Mar 12 | Apr 30 – May 14 | Apr 30 – May 14 | — |
| Basil | Feb 26 – Mar 12 | Apr 16 – Apr 30 | — | — |
| Peas | — | — | Feb 26 – Mar 19 | Aug 9 – Aug 30 |
| Spinach | — | — | Feb 26 – Mar 19 | Sep 6 – Sep 27 |
| Radishes | — | — | Mar 5 – Apr 16 | Sep 20 – Oct 11 |
| Cucumbers | Mar 12 – Mar 19 | Apr 23 – Apr 30 | Apr 16 – Apr 30 | Aug 16 – Aug 30 |
| Zucchini & Summer Squash | Mar 12 – Mar 19 | — | Apr 16 – Apr 30 | Aug 23 – Sep 6 |
| Winter Squash & Pumpkins | Mar 12 – Mar 19 | — | Apr 16 – Apr 30 | — |
| Melons & Watermelon | Mar 12 – Mar 19 | Apr 23 – May 7 | — | — |
| Carrots | — | — | Mar 19 – Apr 16 | Aug 9 – Aug 23 |
| Beets | — | — | Mar 19 – Apr 16 | Aug 23 – Sep 6 |
| Potatoes | — | — | Mar 19 – Apr 9 | — |
| Swiss Chard | — | — | Mar 26 – Apr 23 | Aug 23 – Sep 6 |
| Cilantro | — | — | Mar 26 – Apr 16 | Sep 6 – Sep 27 |
| Green Beans | — | — | Apr 16 – May 7 | Aug 16 – Aug 30 |
| Sweet Corn | — | — | Apr 16 – Apr 30 | — |
| Sweet Potatoes | — | Apr 23 – May 14 | — | — |
| Garlic | — | — | — | Oct 18 – Nov 22 |
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 Harrisburg Cptl Cy Ap, PA weather station, 3 km away (elevation 341 ft (104 m)).
ZIP codes in Harrisburg: 17101 17102 17103 17104 17105 17106 17107 17108 17109 17110 17111 17112 17113 17120 17121 17122 17123 17124 17125 17126 17127 17128 17129 17130 17140 17177
Frost dates near Harrisburg
- New Cumberland Apr 9 · Nov 1
- Lemoyne Apr 15 · Oct 23
- Highspire Apr 9 · Nov 2
- Camp Hill Apr 15 · Oct 23
- Middletown Apr 9 · Nov 2
- Etters Apr 9 · Nov 2
- Enola Apr 15 · Oct 23
- Lewisberry Apr 9 · Nov 1
Frequently asked questions
When is the last frost in Harrisburg, PA?
The median last spring frost in Harrisburg, PA is April 9. There is still about a 10% chance of frost after April 25, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Harrisburg, PA?
The median first fall frost is November 1, with about a 10% chance of frost before October 16.
How long is the growing season in Harrisburg, PA?
About 206 days between the median last spring frost and first fall frost.
What planting zone is Harrisburg, PA?
Harrisburg, PA is in USDA hardiness zone 7a.