When to plant in Superior, WI

Planting dates worked out from Superior's own frost records, not a generic zone chart.

Safe to plant out

May 25

1 year in 10 has a later frost

Average last frost

May 10

about a 50% chance of a later one

Average first fall frost

Oct 7

1 year in 10 by Sep 23

Frost-free days

149

median, 1991–2020

Station used: Superior · 2.5 km away · station 185 m, town 196 m. How we match towns to stations

This season

Plan your garden.

Build my Superior plan

Planting dates for common crops

Crop	Start indoors	Plant out or sow	Harvest from
Tomato	Apr 6 – Apr 20	Jun 1 – Jun 15	Jul 26
Sweet pepper	Mar 23 – Apr 6	Jun 1 – Jun 15	Jul 31
Lettuce (leaf)	Mar 24 – Mar 31	Apr 28 – May 12	Jun 7
Peas	—	Apr 28 – May 26	Jun 22
Bush beans	—	May 26 – Jun 16	Jul 15
Carrot	—	May 9 – Jun 20	Jul 8
Beet	—	May 9 – Jun 20	Jun 28
Potato	—	May 9 – May 30	Jul 18
Kale	Mar 24 – Apr 7	May 5 – May 19	Jun 17
Broccoli	Mar 17 – Mar 31	Apr 28 – May 19	Jun 27
Cucumber	May 4 – May 11	Jun 1 – Jun 15	Jul 21
Summer squash and zucchini	May 4 – May 11	Jun 1 – Jun 15	Jul 16
Winter squash	May 4 – May 11	Jun 1 – Jun 15	Aug 20
Sweet corn	—	May 26 – Jun 16	Jul 25
Onion (from sets)	—	Apr 28 – May 19	Jul 27
Garlic	—	Sep 22 – Oct 20 (fall)	following summer
Spinach	—	Apr 28 – May 26	Jun 5
Basil	Apr 20 – May 4	Jun 1 – Jun 15	Jul 28

Plan all 65 crops for Superior

Superior'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
1910	May 11
1911	May 12
1912	May 19
1913	May 26
1914	May 12
1915	May 18
1916	May 3
1917	May 28
1918	May 13
1919	May 5
1920	May 3
1921	May 16
1922	Apr 28
1923	May 13
1924	May 21
1925	May 17
1926	May 4
1927	Apr 30
1928	Apr 27
1929	May 16
1930	May 18
1931	May 7
1932	Apr 27
1933	May 10
1934	Apr 28
1935	May 4
1936	May 2
1937	May 14
1938	May 12
1939	May 1
1940	May 2
1941	Apr 21
1942	May 15
1943	May 13
1944	May 6
1945	May 10
1946	May 12
1947	Jun 2
1948	Jun 15
1949	May 28
1950	Jun 17
1951	Jun 4
1952	Jun 1
1953	May 19
1954	May 20
1955	May 25
1956	Jun 5
1957	Jun 8
1958	Jun 17
1959	May 22
1960	Jun 9
1961	Jun 15
1962	Jun 21
1963	Jun 21
1964	Jun 16
1965	Jun 17
1966	Jun 10
1968	May 5
1969	May 12
1971	May 9
1972	May 3
1973	May 13
1974	May 26
1975	May 12
1977	May 7
1978	May 21
1979	May 8
1980	May 16
1981	May 20
1982	May 1
1983	May 17
1984	May 11
1985	Apr 16
1986	May 22
1987	May 1
1988	May 25
1989	May 12
1990	May 11
1991	Apr 25
1992	May 26
1993	Apr 21
1994	Jun 10
1995	May 2
1997	May 13
1998	Apr 28
1999	May 10
2000	May 19
2001	Apr 25
2002	May 20
2003	May 22
2004	May 15
2005	May 3
2006	Apr 25
2008	May 26
2009	Apr 29
2011	May 16
2012	May 8
2013	May 23
2014	Apr 27
2016	May 15
2017	Apr 29
2020	May 10
2021	May 11
2022	Apr 29
2023	May 3
2024	Apr 24
2025	May 9

Each year's frost-free daysLong-term trend

See the data as a table

Year	Frost-free days
1910	147
1914	149
1915	141
1916	135
1917	104
1918	130
1919	154
1920	150
1921	133
1922	166
1923	122
1924	130
1925	126
1926	143
1927	159
1928	177
1929	124
1930	151
1931	157
1932	165
1933	155
1934	151
1935	145
1936	151
1937	146
1938	163
1939	147
1940	187
1941	186
1942	132
1943	156
1944	156
1945	141
1946	140
1947	114
1948	99
1949	118
1950	63
1951	111
1952	114
1953	116
1954	125
1955	108
1956	93
1957	100
1958	85
1959	117
1960	100
1961	80
1962	90
1963	83
1965	85
1966	106
1969	157
1971	132
1972	141
1973	129
1974	118
1975	158
1977	147
1978	138
1979	151
1980	129
1981	130
1982	142
1983	128
1984	136
1985	157
1986	136
1987	154
1988	133
1989	136
1990	150
1991	146
1992	125
1993	161
1994	121
1995	142
1997	153
1998	188
2000	127
2001	152
2002	139
2003	129
2004	142
2005	176
2006	167
2009	163
2011	137
2012	151
2013	149
2016	186
2017	163
2020	130
2021	164
2022	151
2023	166
2024	174
2025	151

Each year's average temperature, April to SeptemberLong-term trend

See the data as a table

Year	Growing-season temperature
1910	13.5 °C
1918	11.7 °C
1919	12.9 °C
1920	12.6 °C
1921	14.3 °C
1922	12.9 °C
1923	13.3 °C
1924	12.1 °C
1925	14.0 °C
1926	12.3 °C
1927	12.0 °C
1928	12.5 °C
1929	13.1 °C
1930	14.3 °C
1931	14.2 °C
1932	13.5 °C
1933	13.7 °C
1934	12.9 °C
1935	12.6 °C
1936	13.9 °C
1937	13.9 °C
1938	13.8 °C
1939	13.2 °C
1940	13.2 °C
1941	14.9 °C
1942	13.2 °C
1943	13.5 °C
1944	13.3 °C
1945	13.0 °C
1948	14.8 °C
1949	14.8 °C
1950	11.2 °C
1951	13.0 °C
1952	14.7 °C
1953	13.5 °C
1954	13.2 °C
1955	15.2 °C
1956	12.2 °C
1957	13.1 °C
1958	13.2 °C
1959	14.3 °C
1960	13.6 °C
1961	13.8 °C
1962	12.1 °C
1963	13.8 °C
1965	11.8 °C
1966	13.1 °C
1969	13.4 °C
1970	13.2 °C
1971	12.6 °C
1972	11.2 °C
1973	12.9 °C
1974	11.8 °C
1975	13.2 °C
1976	14.1 °C
1977	12.3 °C
1978	12.8 °C
1979	11.8 °C
1980	13.6 °C
1982	12.2 °C
1983	13.4 °C
1984	12.7 °C
1986	13.1 °C
1987	14.6 °C
1988	14.8 °C
1989	13.3 °C
1991	13.4 °C
1992	12.4 °C
1993	11.8 °C
1994	13.5 °C
1995	12.9 °C
1997	13.0 °C
1998	15.1 °C
2000	13.5 °C
2001	14.0 °C
2002	13.6 °C
2003	13.4 °C
2004	12.6 °C
2005	13.6 °C
2006	15.2 °C
2011	13.4 °C
2012	14.8 °C
2013	12.7 °C
2016	14.7 °C
2017	13.8 °C
2018	14.1 °C
2020	13.9 °C
2021	15.7 °C
2022	13.5 °C
2023	13.8 °C
2024	15.4 °C
2025	14.2 °C

What this means for you: Since 1910, Superior's last spring frost has stayed at about the same time of year. The frost-free season has grown by about 1 days per decade. Year-to-year swings are large, so keep using the safe date rather than the trend.

Source: daily records from Superior (NOAA GHCN-Daily). Years with too many missing days are left out.

Nearby towns

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