When to plant in Hartley, IA

Planting dates worked out from Hartley'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

Apr 29

about a 50% chance of a later one

Average first fall frost

Oct 6

1 year in 10 by Sep 22

Frost-free days

158

median, 1991–2020

Station used: Sanborn · 15.2 km away · station 465 m, town 446 m. How we match towns to stations

This season

Plan your garden.

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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 6 – Mar 13	Apr 10 – Apr 24	May 20
Peas	—	Apr 10 – May 8	Jun 4
Bush beans	—	May 8 – May 29	Jun 27
Carrot	—	Apr 20 – Jun 1	Jun 19
Beet	—	Apr 20 – Jun 1	Jun 9
Potato	—	Apr 20 – May 11	Jun 29
Kale	Mar 6 – Mar 20	Apr 17 – May 1	May 30
Broccoli	Feb 27 – Mar 13	Apr 10 – May 1	Jun 9
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 10 – May 1	Jul 9
Garlic	—	Sep 22 – Oct 20 (fall)	following summer
Spinach	—	Apr 10 – May 8	May 18
Basil	Apr 3 – Apr 17	May 15 – May 29	Jul 11

Plan all 65 crops for Hartley

Hartley'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
1915	May 18
1916	May 18
1917	May 6
1918	May 13
1919	Apr 26
1920	May 3
1921	May 16
1922	Apr 28
1923	May 16
1924	May 24
1925	May 25
1926	May 14
1927	May 15
1928	May 12
1929	May 19
1930	May 17
1931	May 22
1932	May 1
1933	May 3
1934	Apr 27
1936	Apr 29
1937	May 14
1938	May 12
1939	Apr 21
1940	May 3
1941	Apr 24
1942	May 4
1943	May 13
1944	May 6
1945	May 16
1946	May 12
1947	May 29
1948	Apr 13
1949	May 24
1950	May 7
1951	Apr 23
1952	Apr 15
1953	May 13
1954	May 9
1955	May 8
1956	May 4
1957	May 4
1958	Apr 29
1959	May 15
1960	May 11
1961	May 2
1962	Apr 19
1964	Apr 29
1965	May 28
1966	May 12
1967	May 20
1968	May 20
1969	May 11
1970	May 2
1971	May 12
1972	Apr 25
1973	May 15
1974	May 6
1975	May 1
1976	May 7
1977	Apr 8
1978	May 1
1979	May 12
1980	May 8
1981	May 10
1982	Apr 22
1983	Apr 27
1984	May 9
1986	May 2
1987	Apr 11
1988	Apr 27
1989	May 7
1990	May 2
1991	Apr 17
1992	Apr 27
1993	Apr 22
1994	May 2
1995	Apr 28
1996	May 2
1997	May 16
1998	Apr 19
1999	Apr 24
2000	Apr 21
2001	Apr 24
2002	May 3
2003	Apr 10
2004	May 15
2005	May 15
2006	Apr 26
2007	Apr 15
2008	May 3
2009	Apr 21
2010	Apr 9
2011	May 4
2012	Apr 25
2013	May 12
2014	May 17
2015	Apr 23
2016	May 14
2017	May 2
2018	Apr 25
2019	Apr 29
2020	May 8
2021	May 7
2022	Apr 28
2023	May 2
2024	Apr 22
2025	Apr 19
2026	May 7

Each year's frost-free daysLong-term trend

See the data as a table

Year	Frost-free days
1915	139
1916	119
1917	153
1918	127
1919	166
1920	148
1921	136
1922	166
1923	141
1924	126
1925	118
1926	133
1927	127
1928	133
1929	121
1930	133
1931	155
1932	150
1933	157
1934	146
1936	160
1937	145
1938	129
1939	156
1940	144
1941	156
1942	142
1943	153
1944	155
1945	134
1946	139
1947	115
1948	179
1949	111
1950	148
1951	157
1952	160
1953	165
1954	150
1955	158
1956	148
1957	158
1958	154
1959	136
1960	160
1961	148
1962	186
1964	150
1965	118
1966	141
1967	126
1968	135
1969	149
1970	153
1971	133
1972	157
1973	153
1974	119
1975	152
1976	151
1977	179
1978	158
1979	144
1980	147
1981	144
1982	176
1983	146
1984	139
1986	162
1987	173
1988	159
1989	138
1990	143
1991	154
1992	153
1993	157
1994	174
1995	146
1996	153
1997	150
1998	164
1999	148
2000	156
2001	164
2002	156
2003	167
2004	139
2005	144
2006	167
2007	192
2008	165
2009	165
2010	194
2011	163
2012	145
2013	153
2014	139
2015	175
2016	145
2017	161
2018	161
2019	164
2020	158
2021	161
2022	152
2023	158
2024	174
2025	185

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

See the data as a table

Year	Growing-season temperature
1914	19.0 °C
1915	16.0 °C
1916	17.5 °C
1917	16.0 °C
1918	17.1 °C
1919	17.8 °C
1920	16.5 °C
1921	19.0 °C
1922	18.4 °C
1923	17.5 °C
1924	15.8 °C
1925	18.6 °C
1926	17.5 °C
1927	15.9 °C
1928	15.9 °C
1929	16.5 °C
1930	18.0 °C
1931	18.9 °C
1932	17.9 °C
1933	18.3 °C
1934	18.4 °C
1936	19.4 °C
1937	17.9 °C
1938	17.9 °C
1939	18.0 °C
1940	17.5 °C
1941	18.8 °C
1942	17.2 °C
1943	16.9 °C
1944	16.9 °C
1945	15.3 °C
1946	16.8 °C
1947	17.1 °C
1948	18.1 °C
1949	17.3 °C
1950	15.6 °C
1951	15.6 °C
1952	17.6 °C
1953	17.1 °C
1954	17.5 °C
1955	19.6 °C
1956	17.4 °C
1957	16.9 °C
1958	17.3 °C
1959	17.7 °C
1960	16.7 °C
1961	16.4 °C
1962	16.9 °C
1964	17.6 °C
1965	16.7 °C
1966	16.8 °C
1967	16.4 °C
1968	17.1 °C
1969	17.3 °C
1970	18.2 °C
1971	17.4 °C
1972	17.0 °C
1973	17.5 °C
1974	17.2 °C
1975	17.0 °C
1976	18.2 °C
1977	18.9 °C
1978	17.7 °C
1979	16.8 °C
1980	18.3 °C
1981	17.9 °C
1982	17.1 °C
1983	17.8 °C
1984	17.1 °C
1986	17.7 °C
1987	19.1 °C
1988	18.8 °C
1989	17.3 °C
1990	17.0 °C
1991	17.9 °C
1992	15.3 °C
1993	15.3 °C
1994	16.9 °C
1995	16.2 °C
1996	15.7 °C
1997	16.9 °C
1998	18.1 °C
1999	15.1 °C
2000	17.2 °C
2001	17.5 °C
2002	17.5 °C
2003	16.4 °C
2004	15.8 °C
2005	17.5 °C
2006	17.8 °C
2007	18.0 °C
2008	16.4 °C
2009	16.3 °C
2010	18.1 °C
2011	17.1 °C
2012	18.7 °C
2013	16.4 °C
2014	16.3 °C
2015	17.4 °C
2016	17.9 °C
2017	17.4 °C
2018	17.2 °C
2019	16.8 °C
2020	17.5 °C
2021	17.9 °C
2022	17.2 °C
2023	18.2 °C
2024	18.3 °C
2025	18.3 °C

What this means for you: Since 1915, Hartley's last spring frost has come about 1 day earlier per decade, on average. The frost-free season has grown by about 2 days per decade. Year-to-year swings are large, so keep using the safe date rather than the trend.

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

Nearby towns

Sanborn Spencer Paullina Sheldon Milford Sibley