Grampian, PA frost dates
Last spring frostMay 4median date
First fall frostOct 13median date
Growing season162 daysfrost-free
Hardiness zone6aZone 6a
How Grampian compares
- In 8 years out of 10, the last spring frost in Grampian falls between April 20 and May 21, a 31-day window. The first fall frost falls between September 30 and October 28.
- The median last frost is 7 days later than the Pennsylvania median of Apr 27.
- Its 162-day growing season is longer than 28% of the 1,787 Pennsylvania places with a regular frost season (state median 175 days).
- The last frost is 5 days later than the zone 6a median of Apr 29. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 6a chart.
- The weather station records an average of 156 nights a year at or below 32°F.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 20 |
| 50% (median) | May 4 |
| 10% (safe for tender plants) | May 21 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 30 |
| 50% (median) | October 13 |
| 90% (late) | October 28 |
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 Grampian, PA
Grampian, PA frost dates — last frost May 4, first frost Oct 13, zone 6a. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Feb 9 to Feb 23Transplant outside: Apr 6 to Apr 20
Start indoors: Feb 23 to Mar 9Transplant outside: May 18 to Jun 1
Start indoors: Feb 23 to Mar 9Transplant outside: May 18 to Jun 1
Start indoors: Mar 9 to Mar 23Transplant outside: May 11 to May 25
Start indoors: Mar 9 to Mar 23Transplant outside: Apr 13 to Apr 27Sow outdoors: Apr 6 to May 11Plant for fall: Aug 18 to Sep 15
Start indoors: Mar 9 to Mar 23Transplant outside: Apr 6 to Apr 20Sow outdoors: Apr 6 to Apr 20Plant for fall: Aug 4 to Aug 25
Start indoors: Mar 9 to Mar 23Transplant outside: Apr 20 to May 4Plant for fall: Jul 7 to Jul 28
Start indoors: Mar 9 to Mar 23Transplant outside: Apr 13 to Apr 27Plant for fall: Jul 7 to Jul 28
Start indoors: Mar 9 to Mar 23Transplant outside: Apr 20 to May 4Plant for fall: Jul 7 to Jul 28
Start indoors: Mar 23 to Apr 6Transplant outside: May 25 to Jun 8Sow outdoors: May 25 to Jun 8
Start indoors: Mar 23 to Apr 6Transplant outside: May 11 to May 25
Sow outdoors: Mar 23 to Apr 13Plant for fall: Jul 21 to Aug 11
Sow outdoors: Mar 23 to Apr 13Plant for fall: Aug 18 to Sep 8
Sow outdoors: Mar 30 to May 11Plant for fall: Sep 1 to Sep 22
Start indoors: Apr 6 to Apr 13Transplant outside: May 18 to May 25Sow outdoors: May 11 to May 25Plant for fall: Jul 28 to Aug 11
Start indoors: Apr 6 to Apr 13Sow outdoors: May 11 to May 25Plant for fall: Aug 4 to Aug 18
Start indoors: Apr 6 to Apr 13Sow outdoors: May 11 to May 25
Start indoors: Apr 6 to Apr 13Transplant outside: May 18 to Jun 1
Sow outdoors: Apr 13 to May 11Plant for fall: Jul 21 to Aug 4
Sow outdoors: Apr 13 to May 11Plant for fall: Aug 4 to Aug 18
Sow outdoors: Apr 13 to May 4
Sow outdoors: Apr 20 to May 18Plant for fall: Aug 4 to Aug 18
Sow outdoors: Apr 20 to May 11Plant for fall: Aug 18 to Sep 8
Sow outdoors: May 11 to Jun 1Plant for fall: Jul 28 to Aug 11
Sow outdoors: May 11 to May 25
Transplant outside: May 18 to Jun 8
Plant for fall: Sep 29 to Nov 3
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Grampian, PA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 9 – Feb 23 | Apr 6 – Apr 20 | — | — |
| Peppers | Feb 23 – Mar 9 | May 18 – Jun 1 | — | — |
| Eggplant | Feb 23 – Mar 9 | May 18 – Jun 1 | — | — |
| Tomatoes | Mar 9 – Mar 23 | May 11 – May 25 | — | — |
| Lettuce | Mar 9 – Mar 23 | Apr 13 – Apr 27 | Apr 6 – May 11 | Aug 18 – Sep 15 |
| Kale | Mar 9 – Mar 23 | Apr 6 – Apr 20 | Apr 6 – Apr 20 | Aug 4 – Aug 25 |
| Broccoli | Mar 9 – Mar 23 | Apr 20 – May 4 | — | Jul 7 – Jul 28 |
| Cabbage | Mar 9 – Mar 23 | Apr 13 – Apr 27 | — | Jul 7 – Jul 28 |
| Cauliflower | Mar 9 – Mar 23 | Apr 20 – May 4 | — | Jul 7 – Jul 28 |
| Okra | Mar 23 – Apr 6 | May 25 – Jun 8 | May 25 – Jun 8 | — |
| Basil | Mar 23 – Apr 6 | May 11 – May 25 | — | — |
| Peas | — | — | Mar 23 – Apr 13 | Jul 21 – Aug 11 |
| Spinach | — | — | Mar 23 – Apr 13 | Aug 18 – Sep 8 |
| Radishes | — | — | Mar 30 – May 11 | Sep 1 – Sep 22 |
| Cucumbers | Apr 6 – Apr 13 | May 18 – May 25 | May 11 – May 25 | Jul 28 – Aug 11 |
| Zucchini & Summer Squash | Apr 6 – Apr 13 | — | May 11 – May 25 | Aug 4 – Aug 18 |
| Winter Squash & Pumpkins | Apr 6 – Apr 13 | — | May 11 – May 25 | — |
| Melons & Watermelon | Apr 6 – Apr 13 | May 18 – Jun 1 | — | — |
| Carrots | — | — | Apr 13 – May 11 | Jul 21 – Aug 4 |
| Beets | — | — | Apr 13 – May 11 | Aug 4 – Aug 18 |
| Potatoes | — | — | Apr 13 – May 4 | — |
| Swiss Chard | — | — | Apr 20 – May 18 | Aug 4 – Aug 18 |
| Cilantro | — | — | Apr 20 – May 11 | Aug 18 – Sep 8 |
| Green Beans | — | — | May 11 – Jun 1 | Jul 28 – Aug 11 |
| Sweet Corn | — | — | May 11 – May 25 | — |
| Sweet Potatoes | — | May 18 – Jun 8 | — | — |
| Garlic | — | — | — | Sep 29 – Nov 3 |
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 Grampian 1e, PA weather station, 2 km away (elevation 1,509 ft (460 m)).
Frost dates near Grampian
- Curwensville May 4 · Oct 13
- Glen Richey May 4 · Oct 13
- Hyde May 4 · Oct 11
- Olanta May 4 · Oct 13
- Rockton May 4 · Oct 13
- Clearfield May 4 · Oct 11
- New Millport May 4 · Oct 13
- Smokerun May 4 · Oct 11
- Luthersburg May 4 · Oct 13
- Mahaffey May 4 · Oct 13
Frequently asked questions
When is the last frost in Grampian, PA?
The median last spring frost in Grampian, PA is May 4. There is still about a 10% chance of frost after May 21, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Grampian, PA?
The median first fall frost is October 13, with about a 10% chance of frost before September 30.
How long is the growing season in Grampian, PA?
About 162 days between the median last spring frost and first fall frost.
What planting zone is Grampian, PA?
Grampian, PA is in USDA hardiness zone 6a.