Jackson, NH frost dates
Last spring frostMay 18median date
First fall frostOct 1median date
Growing season136 daysfrost-free
Hardiness zone5aZone 5a
How Jackson compares
- In 8 years out of 10, the last spring frost in Jackson falls between May 3 and June 1, a 29-day window. The first fall frost falls between September 15 and October 14.
- The median last frost is 11 days later than the New Hampshire median of May 7.
- Its 136-day growing season is longer than 17% of the 252 New Hampshire places with a regular frost season (state median 150 days).
- The last frost is 15 days later than the zone 5a median of May 3. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 5a chart.
- The weather station records an average of 185 nights a year at or below 32°F.
- Compared with Portland, ME, 93 km away, the last frost here is 22 days later than there and the growing season is 36 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | May 3 |
| 50% (median) | May 18 |
| 10% (safe for tender plants) | June 1 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 15 |
| 50% (median) | October 1 |
| 90% (late) | October 14 |
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 Jackson, NH
Jackson, NH frost dates — last frost May 18, first frost Oct 1, zone 5a. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Feb 23 to Mar 9Transplant outside: Apr 20 to May 4
Start indoors: Mar 9 to Mar 23Transplant outside: Jun 1 to Jun 15
Start indoors: Mar 9 to Mar 23Transplant outside: Jun 1 to Jun 15
Start indoors: Mar 23 to Apr 6Transplant outside: May 25 to Jun 8
Start indoors: Mar 23 to Apr 6Transplant outside: Apr 27 to May 11Sow outdoors: Apr 20 to May 25Plant for fall: Aug 6 to Sep 3
Start indoors: Mar 23 to Apr 6Transplant outside: Apr 20 to May 4Sow outdoors: Apr 20 to May 4Plant for fall: Jul 23 to Aug 13
Start indoors: Mar 23 to Apr 6Transplant outside: May 4 to May 18Plant for fall: Jun 25 to Jul 16
Start indoors: Mar 23 to Apr 6Transplant outside: Apr 27 to May 11Plant for fall: Jun 25 to Jul 16
Start indoors: Mar 23 to Apr 6Transplant outside: May 4 to May 18Plant for fall: Jun 25 to Jul 16
Start indoors: Apr 6 to Apr 20Transplant outside: Jun 8 to Jun 22Sow outdoors: Jun 8 to Jun 22
Start indoors: Apr 6 to Apr 20Transplant outside: May 25 to Jun 8
Sow outdoors: Apr 6 to Apr 27Plant for fall: Jul 9 to Jul 30
Sow outdoors: Apr 6 to Apr 27Plant for fall: Aug 6 to Aug 27
Sow outdoors: Apr 13 to May 25Plant for fall: Aug 20 to Sep 10
Start indoors: Apr 20 to Apr 27Transplant outside: Jun 1 to Jun 8Sow outdoors: May 25 to Jun 8Plant for fall: Jul 16 to Jul 30
Start indoors: Apr 20 to Apr 27Sow outdoors: May 25 to Jun 8Plant for fall: Jul 23 to Aug 6
Start indoors: Apr 20 to Apr 27Sow outdoors: May 25 to Jun 8
Start indoors: Apr 20 to Apr 27Transplant outside: Jun 1 to Jun 15
Sow outdoors: Apr 27 to May 25Plant for fall: Jul 9 to Jul 23
Sow outdoors: Apr 27 to May 25Plant for fall: Jul 23 to Aug 6
Sow outdoors: Apr 27 to May 18
Sow outdoors: May 4 to Jun 1Plant for fall: Jul 23 to Aug 6
Sow outdoors: May 4 to May 25Plant for fall: Aug 6 to Aug 27
Sow outdoors: May 25 to Jun 15Plant for fall: Jul 16 to Jul 30
Sow outdoors: May 25 to Jun 8
Transplant outside: Jun 1 to Jun 22
Plant for fall: Sep 17 to Oct 22
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Jackson, NH
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 23 – Mar 9 | Apr 20 – May 4 | — | — |
| Peppers | Mar 9 – Mar 23 | Jun 1 – Jun 15 | — | — |
| Eggplant | Mar 9 – Mar 23 | Jun 1 – Jun 15 | — | — |
| Tomatoes | Mar 23 – Apr 6 | May 25 – Jun 8 | — | — |
| Lettuce | Mar 23 – Apr 6 | Apr 27 – May 11 | Apr 20 – May 25 | Aug 6 – Sep 3 |
| Kale | Mar 23 – Apr 6 | Apr 20 – May 4 | Apr 20 – May 4 | Jul 23 – Aug 13 |
| Broccoli | Mar 23 – Apr 6 | May 4 – May 18 | — | Jun 25 – Jul 16 |
| Cabbage | Mar 23 – Apr 6 | Apr 27 – May 11 | — | Jun 25 – Jul 16 |
| Cauliflower | Mar 23 – Apr 6 | May 4 – May 18 | — | Jun 25 – Jul 16 |
| Okra | Apr 6 – Apr 20 | Jun 8 – Jun 22 | Jun 8 – Jun 22 | — |
| Basil | Apr 6 – Apr 20 | May 25 – Jun 8 | — | — |
| Peas | — | — | Apr 6 – Apr 27 | Jul 9 – Jul 30 |
| Spinach | — | — | Apr 6 – Apr 27 | Aug 6 – Aug 27 |
| Radishes | — | — | Apr 13 – May 25 | Aug 20 – Sep 10 |
| Cucumbers | Apr 20 – Apr 27 | Jun 1 – Jun 8 | May 25 – Jun 8 | Jul 16 – Jul 30 |
| Zucchini & Summer Squash | Apr 20 – Apr 27 | — | May 25 – Jun 8 | Jul 23 – Aug 6 |
| Winter Squash & Pumpkins | Apr 20 – Apr 27 | — | May 25 – Jun 8 | — |
| Melons & Watermelon | Apr 20 – Apr 27 | Jun 1 – Jun 15 | — | — |
| Carrots | — | — | Apr 27 – May 25 | Jul 9 – Jul 23 |
| Beets | — | — | Apr 27 – May 25 | Jul 23 – Aug 6 |
| Potatoes | — | — | Apr 27 – May 18 | — |
| Swiss Chard | — | — | May 4 – Jun 1 | Jul 23 – Aug 6 |
| Cilantro | — | — | May 4 – May 25 | Aug 6 – Aug 27 |
| Green Beans | — | — | May 25 – Jun 15 | Jul 16 – Jul 30 |
| Sweet Corn | — | — | May 25 – Jun 8 | — |
| Sweet Potatoes | — | Jun 1 – Jun 22 | — | — |
| Garlic | — | — | — | Sep 17 – Oct 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 Pinkham Notch, NH weather station, 11 km away (elevation 2,024 ft (617 m)).
Frost dates near Jackson
- Glen May 7 · Oct 5
- Intervale May 7 · Oct 5
- Kearsarge May 7 · Oct 5
- Bartlett May 7 · Oct 5
- North Conway May 7 · Oct 5
- Conway May 7 · Oct 5
- Center Conway May 17 · Sep 25
- Bretton Woods frost any month
- Randolph May 14 · Sep 26
- Gorham May 14 · Sep 26
Frequently asked questions
When is the last frost in Jackson, NH?
The median last spring frost in Jackson, NH is May 18. There is still about a 10% chance of frost after June 1, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Jackson, NH?
The median first fall frost is October 1, with about a 10% chance of frost before September 15.
How long is the growing season in Jackson, NH?
About 136 days between the median last spring frost and first fall frost.
What planting zone is Jackson, NH?
Jackson, NH is in USDA hardiness zone 5a.