When to plant in Grafton, WI
Planting dates worked out from Grafton's own frost records, not a generic zone chart.
Safe to plant out
May 3
1 year in 10 has a later frost
Average last frost
Apr 25
about a 50% chance of a later one
Average first fall frost
Oct 17
1 year in 10 by Oct 2
Frost-free days
179
median, 1991–2020
Station used: Port Washington · 11.0 km away · station 181 m, town 231 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 26 – Apr 9 | May 21 – Jun 4 | Jul 15 |
| Sweet pepper | Mar 12 – Mar 26 | May 21 – Jun 4 | Jul 20 |
| Lettuce (leaf) | Mar 10 – Mar 17 | Apr 14 – Apr 28 | May 24 |
| Peas | — | Apr 14 – May 12 | Jun 8 |
| Bush beans | — | May 14 – Jun 4 | Jul 3 |
| Carrot | — | Apr 25 – Jun 6 | Jun 24 |
| Beet | — | Apr 25 – Jun 6 | Jun 14 |
| Potato | — | Apr 25 – May 16 | Jul 4 |
| Kale | Mar 10 – Mar 24 | Apr 21 – May 5 | Jun 3 |
| Broccoli | Mar 3 – Mar 17 | Apr 14 – May 5 | Jun 13 |
| Cucumber | Apr 23 – Apr 30 | May 21 – Jun 4 | Jul 10 |
| Summer squash and zucchini | Apr 23 – Apr 30 | May 21 – Jun 4 | Jul 5 |
| Winter squash | Apr 23 – Apr 30 | May 21 – Jun 4 | Aug 9 |
| Sweet corn | — | May 14 – Jun 4 | Jul 13 |
| Onion (from sets) | — | Apr 14 – May 5 | Jul 13 |
| Garlic | — | Oct 3 – Oct 31 (fall) | following summer |
| Spinach | — | Apr 14 – May 12 | May 22 |
| Basil | Apr 9 – Apr 23 | May 21 – Jun 4 | Jul 17 |
Grafton'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 |
|---|---|
| 1894 | Apr 22 |
| 1895 | May 26 |
| 1896 | Apr 20 |
| 1898 | May 5 |
| 1899 | Apr 17 |
| 1900 | May 9 |
| 1901 | May 25 |
| 1902 | May 27 |
| 1905 | May 25 |
| 1906 | May 8 |
| 1907 | May 18 |
| 1908 | May 2 |
| 1909 | May 4 |
| 1910 | May 14 |
| 1911 | May 3 |
| 1913 | May 11 |
| 1914 | Jun 17 |
| 1916 | Apr 29 |
| 1917 | May 23 |
| 1918 | May 1 |
| 1919 | Apr 26 |
| 1920 | May 16 |
| 1921 | May 15 |
| 1922 | Apr 29 |
| 1923 | May 13 |
| 1924 | May 20 |
| 1925 | May 26 |
| 1926 | May 20 |
| 1927 | Apr 30 |
| 1928 | May 12 |
| 1960 | Apr 18 |
| 1961 | May 27 |
| 1962 | Apr 21 |
| 1963 | May 1 |
| 1964 | Apr 9 |
| 1965 | Apr 28 |
| 1966 | May 13 |
| 1967 | May 12 |
| 1968 | Apr 29 |
| 1969 | Apr 30 |
| 1970 | Apr 13 |
| 1971 | May 3 |
| 1972 | May 7 |
| 1973 | Apr 14 |
| 1974 | May 7 |
| 1975 | May 13 |
| 1976 | May 6 |
| 1977 | May 9 |
| 1978 | Apr 22 |
| 1979 | May 9 |
| 1980 | May 9 |
| 1981 | May 2 |
| 1982 | Apr 28 |
| 1988 | Apr 28 |
| 1989 | Apr 20 |
| 1990 | Apr 19 |
| 1991 | Apr 12 |
| 1992 | Apr 28 |
| 1993 | Apr 27 |
| 1994 | Apr 30 |
| 1995 | Apr 24 |
| 1996 | Apr 28 |
| 1997 | Apr 18 |
| 1998 | Apr 6 |
| 1999 | Apr 25 |
| 2000 | Apr 20 |
| 2001 | Apr 18 |
| 2002 | May 21 |
| 2003 | Jun 1 |
| 2004 | May 3 |
| 2005 | Apr 29 |
| 2006 | Apr 9 |
| 2007 | Apr 16 |
| 2008 | May 1 |
| 2009 | Apr 15 |
| 2010 | Apr 28 |
| 2011 | Apr 21 |
Each year's frost-free daysLong-term trend
See the data as a table
| Year | Frost-free days |
|---|---|
| 1894 | 168 |
| 1895 | 125 |
| 1898 | 161 |
| 1899 | 160 |
| 1902 | 105 |
| 1905 | 138 |
| 1907 | 141 |
| 1908 | 150 |
| 1910 | 166 |
| 1911 | 176 |
| 1916 | 163 |
| 1917 | 137 |
| 1918 | 183 |
| 1919 | 173 |
| 1920 | 137 |
| 1921 | 145 |
| 1922 | 166 |
| 1923 | 123 |
| 1924 | 132 |
| 1925 | 136 |
| 1926 | 128 |
| 1927 | 185 |
| 1960 | 184 |
| 1961 | 151 |
| 1962 | 184 |
| 1963 | 184 |
| 1964 | 171 |
| 1965 | 179 |
| 1966 | 159 |
| 1967 | 149 |
| 1968 | 158 |
| 1969 | 167 |
| 1970 | 185 |
| 1971 | 184 |
| 1972 | 160 |
| 1973 | 202 |
| 1974 | 137 |
| 1975 | 168 |
| 1976 | 138 |
| 1977 | 159 |
| 1978 | 177 |
| 1979 | 156 |
| 1980 | 148 |
| 1981 | 168 |
| 1982 | 150 |
| 1988 | 158 |
| 1989 | 195 |
| 1990 | 182 |
| 1991 | 185 |
| 1993 | 155 |
| 1994 | 179 |
| 1995 | 151 |
| 1996 | 164 |
| 1997 | 186 |
| 1998 | 211 |
| 1999 | 181 |
| 2000 | 168 |
| 2001 | 171 |
| 2002 | 147 |
| 2003 | 122 |
| 2004 | 154 |
| 2005 | 181 |
| 2006 | 185 |
| 2007 | 204 |
| 2008 | 179 |
| 2009 | 178 |
| 2010 | 183 |
| 2011 | 202 |
Each year's average temperature, April to SeptemberLong-term trend
See the data as a table
| Year | Growing-season temperature |
|---|---|
| 1894 | 16.1 °C |
| 1895 | 16.4 °C |
| 1896 | 16.3 °C |
| 1898 | 15.8 °C |
| 1899 | 15.5 °C |
| 1900 | 15.8 °C |
| 1902 | 14.1 °C |
| 1908 | 16.0 °C |
| 1910 | 16.1 °C |
| 1911 | 16.3 °C |
| 1913 | 15.4 °C |
| 1914 | 15.6 °C |
| 1915 | 14.1 °C |
| 1916 | 14.6 °C |
| 1917 | 13.8 °C |
| 1918 | 14.3 °C |
| 1919 | 16.6 °C |
| 1920 | 14.4 °C |
| 1921 | 17.5 °C |
| 1922 | 15.8 °C |
| 1923 | 14.8 °C |
| 1924 | 13.6 °C |
| 1925 | 16.3 °C |
| 1926 | 15.0 °C |
| 1927 | 15.2 °C |
| 1960 | 15.1 °C |
| 1961 | 14.8 °C |
| 1962 | 14.7 °C |
| 1963 | 14.7 °C |
| 1964 | 15.3 °C |
| 1965 | 14.2 °C |
| 1966 | 15.0 °C |
| 1967 | 13.6 °C |
| 1968 | 15.0 °C |
| 1969 | 15.0 °C |
| 1970 | 15.9 °C |
| 1971 | 15.7 °C |
| 1972 | 15.4 °C |
| 1973 | 16.2 °C |
| 1974 | 14.9 °C |
| 1975 | 15.2 °C |
| 1976 | 15.6 °C |
| 1977 | 15.4 °C |
| 1978 | 14.9 °C |
| 1979 | 14.3 °C |
| 1980 | 15.2 °C |
| 1981 | 15.2 °C |
| 1983 | 16.0 °C |
| 1987 | 16.5 °C |
| 1988 | 17.0 °C |
| 1989 | 16.0 °C |
| 1990 | 15.2 °C |
| 1991 | 16.6 °C |
| 1993 | 14.5 °C |
| 1994 | 15.4 °C |
| 1995 | 15.3 °C |
| 1996 | 14.0 °C |
| 1997 | 13.9 °C |
| 1998 | 17.1 °C |
| 1999 | 16.1 °C |
| 2000 | 14.9 °C |
| 2001 | 16.0 °C |
| 2002 | 15.9 °C |
| 2003 | 15.2 °C |
| 2004 | 15.0 °C |
| 2005 | 16.6 °C |
| 2006 | 16.3 °C |
| 2007 | 16.0 °C |
| 2008 | 15.6 °C |
| 2009 | 14.9 °C |
| 2010 | 16.7 °C |
| 2011 | 15.4 °C |
What this means for you: Since 1894, Grafton's last spring frost has come about 2 days earlier per decade, on average. The frost-free season has grown by about 3 days per decade. Year-to-year swings are large, so keep using the safe date rather than the trend.
Source: daily records from Port Washington (NOAA GHCN-Daily). Years with too many missing days are left out.