Williamsburg, PA frost dates
How Williamsburg compares
- In 8 years out of 10, the last spring frost in Williamsburg falls between April 8 and May 11, a 33-day window. The first fall frost falls between October 5 and November 4.
- The median last frost is 4 days earlier than the Pennsylvania median of Apr 27.
- Its 181-day growing season is longer than 63% of the 1,787 Pennsylvania places with a regular frost season (state median 175 days).
- The last frost is typical for zone 6b, where the median is Apr 22.
- The weather station records an average of 118 nights a year at or below 32°F.
- Compared with Harrisburg, PA, 119 km away, the last frost here is 8 days later than there and the growing season is 10 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 8 |
| 50% (median) | April 23 |
| 10% (safe for tender plants) | May 11 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 5 |
| 50% (median) | October 21 |
| 90% (late) | November 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 Williamsburg, PA
Williamsburg, PA frost dates — last frost Apr 23, first frost Oct 21, zone 6b. whenisthelastfrost.com
When to plant vegetables in Williamsburg, PA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 29 – Feb 12 | Mar 26 – Apr 9 | — | — |
| Peppers | Feb 12 – Feb 26 | May 7 – May 21 | — | — |
| Eggplant | Feb 12 – Feb 26 | May 7 – May 21 | — | — |
| Tomatoes | Feb 26 – Mar 12 | Apr 30 – May 14 | — | — |
| Lettuce | Feb 26 – Mar 12 | Apr 2 – Apr 16 | Mar 26 – Apr 30 | Aug 26 – Sep 23 |
| Kale | Feb 26 – Mar 12 | Mar 26 – Apr 9 | Mar 26 – Apr 9 | Aug 12 – Sep 2 |
| Broccoli | Feb 26 – Mar 12 | Apr 9 – Apr 23 | — | Jul 15 – Aug 5 |
| Cabbage | Feb 26 – Mar 12 | Apr 2 – Apr 16 | — | Jul 15 – Aug 5 |
| Cauliflower | Feb 26 – Mar 12 | Apr 9 – Apr 23 | — | Jul 15 – Aug 5 |
| Okra | Mar 12 – Mar 26 | May 14 – May 28 | May 14 – May 28 | — |
| Basil | Mar 12 – Mar 26 | Apr 30 – May 14 | — | — |
| Peas | — | — | Mar 12 – Apr 2 | Jul 29 – Aug 19 |
| Spinach | — | — | Mar 12 – Apr 2 | Aug 26 – Sep 16 |
| Radishes | — | — | Mar 19 – Apr 30 | Sep 9 – Sep 30 |
| Cucumbers | Mar 26 – Apr 2 | May 7 – May 14 | Apr 30 – May 14 | Aug 5 – Aug 19 |
| Zucchini & Summer Squash | Mar 26 – Apr 2 | — | Apr 30 – May 14 | Aug 12 – Aug 26 |
| Winter Squash & Pumpkins | Mar 26 – Apr 2 | — | Apr 30 – May 14 | — |
| Melons & Watermelon | Mar 26 – Apr 2 | May 7 – May 21 | — | — |
| Carrots | — | — | Apr 2 – Apr 30 | Jul 29 – Aug 12 |
| Beets | — | — | Apr 2 – Apr 30 | Aug 12 – Aug 26 |
| Potatoes | — | — | Apr 2 – Apr 23 | — |
| Swiss Chard | — | — | Apr 9 – May 7 | Aug 12 – Aug 26 |
| Cilantro | — | — | Apr 9 – Apr 30 | Aug 26 – Sep 16 |
| Green Beans | — | — | Apr 30 – May 21 | Aug 5 – Aug 19 |
| Sweet Corn | — | — | Apr 30 – May 14 | — |
| Sweet Potatoes | — | May 7 – May 28 | — | — |
| Garlic | — | — | — | Oct 7 – Nov 11 |
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 Altoona Blair Co Ap, PA weather station, 13 km away (elevation 1,480 ft (451 m)).
Frost dates near Williamsburg
- James Creek Apr 19 · Oct 28
- Entriken Apr 23 · Oct 21
- Hollidaysburg Apr 25 · Oct 20
- Hesston Apr 19 · Oct 28
- Martinsburg Apr 23 · Oct 21
- Roaring Spring Apr 23 · Oct 21
- Newry Apr 25 · Oct 20
- Duncansville Apr 25 · Oct 20
- Curryville Apr 23 · Oct 21
- Altoona Apr 25 · Oct 21
Frequently asked questions
When is the last frost in Williamsburg, PA?
The median last spring frost in Williamsburg, PA is April 23. There is still about a 10% chance of frost after May 11, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Williamsburg, PA?
The median first fall frost is October 21, with about a 10% chance of frost before October 5.
How long is the growing season in Williamsburg, PA?
About 181 days between the median last spring frost and first fall frost.
What planting zone is Williamsburg, PA?
Williamsburg, PA is in USDA hardiness zone 6b.