When to plant in Boxborough, MA
Planting dates worked out from Boxborough's own frost records, not a generic zone chart.
Safe to plant out
May 15
1 year in 10 has a later frost
Average last frost
May 3
about a 50% chance of a later one
Average first fall frost
Oct 8
1 year in 10 by Sep 28
Frost-free days
154
median, 1991–2020
Station used: Maynard 2 · 9.8 km away · station 62 m, town 138 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 | Mar 20 – Apr 3 | May 15 – May 29 | Jul 9 |
| Sweet pepper | Mar 6 – Mar 20 | May 15 – May 29 | Jul 14 |
| Lettuce (leaf) | Mar 1 – Mar 8 | Apr 5 – Apr 19 | May 15 |
| Peas | — | Apr 3 – May 1 | May 28 |
| Bush beans | — | May 8 – May 29 | Jun 27 |
| Carrot | — | Apr 12 – May 24 | Jun 11 |
| Beet | — | Apr 11 – May 23 | May 31 |
| Potato | — | Apr 12 – May 3 | Jun 21 |
| Kale | Feb 27 – Mar 13 | Apr 10 – Apr 24 | May 23 |
| Broccoli | Feb 22 – Mar 8 | Apr 5 – Apr 26 | Jun 4 |
| Cucumber | Apr 17 – Apr 24 | May 15 – May 29 | Jul 4 |
| Summer squash and zucchini | Apr 17 – Apr 24 | May 15 – May 29 | Jun 29 |
| Winter squash | Apr 17 – Apr 24 | May 15 – May 29 | Aug 3 |
| Sweet corn | — | May 8 – May 29 | Jul 7 |
| Onion (from sets) | — | Apr 5 – Apr 26 | Jul 4 |
| Garlic | — | Sep 24 – Oct 22 (fall) | following summer |
| Spinach | — | Apr 3 – May 1 | May 11 |
| Basil | Apr 3 – Apr 17 | May 15 – May 29 | Jul 11 |
Boxborough'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 |
|---|---|
| 1964 | Jun 6 |
| 1966 | May 16 |
| 1967 | May 14 |
| 1968 | May 28 |
| 1970 | Apr 21 |
| 1971 | May 15 |
| 1972 | May 26 |
| 1973 | Apr 15 |
| 1975 | May 1 |
| 1977 | May 10 |
| 1978 | May 4 |
| 1979 | Apr 21 |
| 1980 | Apr 22 |
| 1981 | May 21 |
| 1982 | Apr 30 |
| 1983 | May 18 |
| 1984 | May 3 |
| 1985 | May 9 |
| 1986 | May 10 |
| 1987 | May 14 |
| 1988 | May 9 |
| 1989 | Apr 26 |
| 1990 | Apr 20 |
| 1991 | Apr 20 |
| 1992 | May 7 |
| 1993 | Apr 30 |
| 1994 | Apr 23 |
| 1995 | May 2 |
| 1996 | May 14 |
| 1997 | Apr 16 |
| 1998 | Apr 26 |
| 1999 | May 1 |
| 2000 | May 3 |
| 2001 | May 8 |
| 2002 | May 21 |
| 2003 | May 18 |
| 2004 | May 5 |
| 2005 | May 5 |
| 2006 | Apr 30 |
| 2007 | May 7 |
| 2008 | May 2 |
| 2009 | Apr 20 |
Each year's frost-free daysLong-term trend
See the data as a table
| Year | Frost-free days |
|---|---|
| 1964 | 101 |
| 1966 | 133 |
| 1967 | 146 |
| 1968 | 130 |
| 1970 | 167 |
| 1971 | 150 |
| 1972 | 128 |
| 1973 | 159 |
| 1977 | 149 |
| 1978 | 145 |
| 1979 | 151 |
| 1980 | 155 |
| 1981 | 141 |
| 1982 | 163 |
| 1983 | 151 |
| 1984 | 155 |
| 1985 | 155 |
| 1986 | 129 |
| 1987 | 151 |
| 1988 | 150 |
| 1989 | 166 |
| 1990 | 183 |
| 1991 | 154 |
| 1992 | 146 |
| 1993 | 142 |
| 1994 | 170 |
| 1995 | 149 |
| 1996 | 142 |
| 1997 | 188 |
| 1998 | 162 |
| 1999 | 157 |
| 2000 | 148 |
| 2001 | 152 |
| 2002 | 146 |
| 2003 | 137 |
| 2004 | 153 |
| 2005 | 169 |
| 2006 | 166 |
| 2007 | 174 |
| 2008 | 170 |
| 2009 | 174 |
Each year's average temperature, April to SeptemberLong-term trend
See the data as a table
| Year | Growing-season temperature |
|---|---|
| 1964 | 16.4 °C |
| 1966 | 16.2 °C |
| 1967 | 16.3 °C |
| 1968 | 16.8 °C |
| 1970 | 17.0 °C |
| 1971 | 16.7 °C |
| 1972 | 16.0 °C |
| 1973 | 17.5 °C |
| 1976 | 16.8 °C |
| 1978 | 17.3 °C |
| 1979 | 17.2 °C |
| 1980 | 17.5 °C |
| 1981 | 17.4 °C |
| 1982 | 16.3 °C |
| 1983 | 18.4 °C |
| 1984 | 17.1 °C |
| 1985 | 17.6 °C |
| 1986 | 16.3 °C |
| 1987 | 17.5 °C |
| 1988 | 17.1 °C |
| 1989 | 17.5 °C |
| 1990 | 16.9 °C |
| 1991 | 18.2 °C |
| 1992 | 16.4 °C |
| 1993 | 17.7 °C |
| 1994 | 17.9 °C |
| 1995 | 17.2 °C |
| 1996 | 17.4 °C |
| 1997 | 17.0 °C |
| 1998 | 18.4 °C |
| 1999 | 18.4 °C |
| 2000 | 16.2 °C |
| 2001 | 17.8 °C |
| 2002 | 18.0 °C |
| 2003 | 16.8 °C |
| 2004 | 17.0 °C |
| 2005 | 17.6 °C |
| 2006 | 17.2 °C |
| 2007 | 17.0 °C |
| 2008 | 16.9 °C |
What this means for you: Since 1964, Boxborough's last spring frost has come about 3 days earlier per decade, on average. The frost-free season has grown by about 6 days per decade. Year-to-year swings are large, so keep using the safe date rather than the trend.
Source: daily records from Maynard 2 (NOAA GHCN-Daily). Years with too many missing days are left out.