Frost dates for Greenland, NH
At Greenland, the median last spring frost (32°F) is May 4 and the median first fall frost is Oct 8, for a typical growing season of 157 days. For a 90% chance that the last frost has passed, wait until May 18. Nearby ZIP codes are in USDA hardiness zones 6a to 6b.
- May 4Last spring frost (median)50% chance of 32°F after this date
- May 18Safer planting date10% chance of 32°F after this date
- Oct 8First fall frost (median)50% chance of 32°F by this date
- 157 daysGrowing season (median)between 32°F freezes
Last spring frost dates
The chance that the temperature drops to the threshold after each date.
| Temperature | 90% chance later | 50% chance later | 10% chance later |
|---|---|---|---|
| 36°F | May 3 | May 16 | May 29 |
| 32°F | Apr 23 | May 4 | May 18 |
| 28°F | Apr 7 | Apr 23 | May 7 |
| 24°F | Mar 27 | Apr 7 | Apr 23 |
First fall frost dates
The chance that the temperature has dropped to the threshold by each date.
| Temperature | 10% chance by | 50% chance by | 90% chance by |
|---|---|---|---|
| 36°F | Sep 16 | Sep 30 | Oct 10 |
| 32°F | Sep 27 | Oct 8 | Oct 24 |
| 28°F | Oct 5 | Oct 21 | Nov 5 |
| 24°F | Oct 18 | Nov 3 | Nov 18 |
Growing season length
Days between the last spring and first fall freeze, as the length reached in 9, 5 and 1 out of 10 years.
| Temperature | 9 in 10 years at least | 5 in 10 years at least | 1 in 10 years at least |
|---|---|---|---|
| 36°F | 115 days | 134 days | 154 days |
| 32°F | 138 days | 157 days | 174 days |
| 28°F | 158 days | 180 days | 201 days |
| 24°F | 187 days | 209 days | 229 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 03840 | 6a | -10 to -5°F | 3 km |
| 03862 | 6a | -10 to -5°F | 5 km |
| 03870 | 6a | -10 to -5°F | 5 km |
| 03871 | 6a | -10 to -5°F | 6 km |
| 03801 | 6a | -10 to -5°F | 6 km |
| 03885 | 6a | -10 to -5°F | 6 km |
| 03842 | 6a | -10 to -5°F | 9 km |
| 03854 | 6a | -10 to -5°F | 10 km |
| 03844 | 6b | -5 to 0°F | 12 km |
| 03904 | 6a | -10 to -5°F | 12 km |
| 03874 | 6b | -5 to 0°F | 16 km |
| 03905 | 6b | -5 to 0°F | 18 km |
| 01952 | 6b | -5 to 0°F | 20 km |
Not the official USDA Plant Hardiness Zone Map. Zones shown here are the values published in the USDA-ARS / Oregon State University PRISM Group 2023 ZIP code tables, shown unaltered. For the official interactive map, visit planthardiness.ars.usda.gov.
About this station
- NOAA station ID USC00273626, at 43.0211, -70.8258, elevation 29 m (95 ft).
- Data quality: Standard (24+ years of data), 27 years of freeze data.
- Average days per year at or below 32°F: 143.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Durham 2 SSW (14 km)
- Durham (17 km)
- Durham 2 N (19 km)
- Epping (21 km)
- Rochester Skyhaven Airport (30 km)
- W Hampstead (33 km)
- Massabesic Lake (46 km)
- Manchester Airport (51 km)
Sources
- NOAA National Centers for Environmental Information, U.S. Climate Normals 1991–2020, annual/seasonal normals by station (version 1.0.1), file dated June 27, 2023; documentation.
- USDA Agricultural Research Service and PRISM Group, Oregon State University, 2023 Plant Hardiness Zone Map ZIP code tables (CONUS, Alaska, Hawaii, Puerto Rico), files dated November 17, 2023. Data © PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed November 1, 2026. Official map: planthardiness.ars.usda.gov.
- U.S. Census Bureau, 2024 Gazetteer ZIP Code Tabulation Areas file, dated August 30, 2024 (ZIP centroids used to find the nearest station).
Freeze dates are 30-year probabilities, not forecasts. Check your local forecast before planting tender plants.