When to plant in Jefferson, NH
Planting dates worked out from Jefferson's own frost records, not a generic zone chart.
Safe to plant out
Jun 5
1 year in 10 has a later frost
Average last frost
May 25
about a 50% chance of a later one
Average first fall frost
Sep 19
1 year in 10 by Sep 11
Frost-free days
116
median, 1991–2020
Station used: York Pond · 14.8 km away · station 463 m, town 425 m. How we match towns to stations
This season
Plan your garden.
Planting dates for common crops
| Crop | Start indoors | Plant out or sow | Harvest from |
|---|---|---|---|
| Tomato | Apr 10 – Apr 24 | Jun 5 – Jun 19 | Jul 30 |
| Sweet pepper | Mar 27 – Apr 10 | Jun 5 – Jun 19 | Aug 4 |
| Lettuce (leaf) | Mar 23 – Mar 30 | Apr 27 – May 11 | Jun 6 |
| Peas | — | Apr 25 – May 23 | Jun 19 |
| Bush beans | — | May 29 – Jun 19 | Jul 18 |
| Carrot | — | May 4 – Jun 15 | Jul 3 |
| Beet | — | May 4 – Jun 15 | Jun 23 |
| Potato | — | May 4 – May 25 | Jul 13 |
| Kale | Mar 21 – Apr 4 | May 2 – May 16 | Jun 14 |
| Broccoli | Mar 16 – Mar 30 | Apr 27 – May 18 | Jun 26 |
| Cucumber | May 8 – May 15 | Jun 5 – Jun 19 | Jul 25 |
| Summer squash and zucchini | May 8 – May 15 | Jun 5 – Jun 19 | Jul 20 |
| Winter squash | May 8 – May 15 | Jun 5 – Jun 19 | Aug 24 |
| Sweet corn | — | May 29 – Jun 19 | Jul 28 |
| Onion (from sets) | — | Apr 27 – May 18 | Jul 26 |
| Garlic | — | Sep 5 – Oct 3 (fall) | following summer |
| Spinach | — | Apr 25 – May 23 | Jun 2 |
| Basil | Apr 24 – May 8 | Jun 5 – Jun 19 | Aug 1 |
Jefferson's weather over time
How the growing season has shifted here, year by year, from the station's own records.
Each year's last spring frostLong-term trend
See the data as a table
| Year | Last spring frost |
|---|---|
| 1990 | Jun 6 |
| 1991 | May 20 |
| 1992 | May 26 |
| 1993 | Jun 5 |
| 1994 | May 28 |
| 1995 | May 9 |
| 1996 | May 28 |
| 1997 | May 28 |
| 1998 | May 27 |
| 1999 | May 14 |
| 2001 | Jun 1 |
| 2002 | Jun 4 |
| 2003 | May 18 |
| 2004 | Jun 11 |
| 2005 | May 21 |
| 2006 | May 25 |
| 2007 | May 22 |
| 2008 | May 11 |
| 2009 | May 26 |
| 2010 | May 13 |
| 2011 | May 9 |
| 2012 | May 12 |
| 2013 | May 27 |
| 2014 | May 29 |
| 2015 | Jun 7 |
| 2016 | May 17 |
| 2017 | Jun 28 |
| 2018 | May 18 |
| 2019 | May 17 |
| 2020 | Jun 2 |
| 2021 | May 28 |
| 2022 | May 27 |
| 2023 | May 26 |
| 2024 | Apr 28 |
| 2026 | May 31 |
Each year's frost-free daysLong-term trend
See the data as a table
| Year | Frost-free days |
|---|---|
| 1990 | 93 |
| 1991 | 123 |
| 1992 | 116 |
| 1993 | 106 |
| 1994 | 98 |
| 1995 | 124 |
| 1997 | 116 |
| 1998 | 119 |
| 1999 | 127 |
| 2001 | 105 |
| 2002 | 116 |
| 2003 | 136 |
| 2004 | 110 |
| 2005 | 125 |
| 2006 | 108 |
| 2007 | 117 |
| 2008 | 122 |
| 2009 | 116 |
| 2010 | 127 |
| 2011 | 130 |
| 2012 | 130 |
| 2013 | 112 |
| 2014 | 106 |
| 2015 | 111 |
| 2016 | 131 |
| 2017 | 94 |
| 2018 | 113 |
| 2019 | 124 |
| 2020 | 104 |
| 2021 | 123 |
| 2022 | 125 |
| 2023 | 138 |
| 2024 | 171 |
Each year's average temperature, April to SeptemberLong-term trend
See the data as a table
| Year | Growing-season temperature |
|---|---|
| 1989 | 12.6 °C |
| 1990 | 12.9 °C |
| 1991 | 13.3 °C |
| 1992 | 12.1 °C |
| 1993 | 13.3 °C |
| 1994 | 13.0 °C |
| 1995 | 12.7 °C |
| 1996 | 13.1 °C |
| 1997 | 11.8 °C |
| 1998 | 14.0 °C |
| 1999 | 14.3 °C |
| 2002 | 13.6 °C |
| 2003 | 13.2 °C |
| 2004 | 13.1 °C |
| 2005 | 13.7 °C |
| 2006 | 13.6 °C |
| 2009 | 12.8 °C |
| 2010 | 14.4 °C |
| 2011 | 13.7 °C |
| 2012 | 13.8 °C |
| 2013 | 13.3 °C |
| 2014 | 12.7 °C |
| 2015 | 13.4 °C |
| 2016 | 13.3 °C |
| 2017 | 13.1 °C |
| 2018 | 13.3 °C |
| 2019 | 12.6 °C |
| 2020 | 13.1 °C |
| 2021 | 13.5 °C |
| 2022 | 13.0 °C |
| 2023 | 13.2 °C |
| 2024 | 14.3 °C |
What this means for you: Since 1990, Jefferson's last spring frost has come about 1 day earlier per decade, on average. The frost-free season has grown by about 5 days per decade. Year-to-year swings are large, so keep using the safe date rather than the trend.
Source: daily records from York Pond (NOAA GHCN-Daily). Years with too many missing days are left out.