When to plant in Herscher, IL
Planting dates worked out from Herscher's own frost records, not a generic zone chart.
Safe to plant out
May 4
1 year in 10 has a later frost
Average last frost
Apr 21
about a 50% chance of a later one
Average first fall frost
Oct 17
1 year in 10 by Oct 1
Frost-free days
178
median, 1991–2020
Station used: Kankakee Wwtp · 20.2 km away · station 183 m, town 201 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 9 – Mar 23 | May 4 – May 18 | Jun 28 |
| Sweet pepper | Feb 23 – Mar 9 | May 4 – May 18 | Jul 3 |
| Lettuce (leaf) | Feb 20 – Feb 27 | Mar 27 – Apr 10 | May 6 |
| Peas | — | Mar 27 – Apr 24 | May 21 |
| Bush beans | — | Apr 27 – May 18 | Jun 16 |
| Carrot | — | Apr 5 – May 17 | Jun 4 |
| Beet | — | Apr 5 – May 17 | May 25 |
| Potato | — | Apr 5 – Apr 26 | Jun 14 |
| Kale | Feb 20 – Mar 6 | Apr 3 – Apr 17 | May 16 |
| Broccoli | Feb 13 – Feb 27 | Mar 27 – Apr 17 | May 26 |
| Cucumber | Apr 6 – Apr 13 | May 4 – May 18 | Jun 23 |
| Summer squash and zucchini | Apr 6 – Apr 13 | May 4 – May 18 | Jun 18 |
| Winter squash | Apr 6 – Apr 13 | May 4 – May 18 | Jul 23 |
| Sweet corn | — | Apr 27 – May 18 | Jun 26 |
| Onion (from sets) | — | Mar 27 – Apr 17 | Jun 25 |
| Garlic | — | Oct 3 – Oct 31 (fall) | following summer |
| Spinach | — | Mar 27 – Apr 24 | May 4 |
| Basil | Mar 23 – Apr 6 | May 4 – May 18 | Jun 30 |
Herscher'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 |
|---|---|
| 1974 | Apr 25 |
| 1975 | Apr 14 |
| 1976 | Apr 13 |
| 1977 | Apr 9 |
| 1978 | May 2 |
| 1979 | Apr 11 |
| 1980 | Apr 17 |
| 1981 | May 12 |
| 1982 | Apr 22 |
| 1983 | May 9 |
| 1984 | Apr 23 |
| 1985 | Apr 10 |
| 1986 | May 3 |
| 1987 | Apr 10 |
| 1988 | Apr 24 |
| 1989 | May 7 |
| 1990 | Apr 18 |
| 1991 | Apr 12 |
| 1992 | May 27 |
| 1993 | Apr 22 |
| 1994 | Apr 7 |
| 1995 | May 3 |
| 1996 | Apr 27 |
| 1997 | Apr 19 |
| 1998 | Apr 17 |
| 1999 | Mar 29 |
| 2000 | Apr 13 |
| 2001 | Apr 26 |
| 2002 | Apr 28 |
| 2003 | Apr 24 |
| 2004 | Apr 15 |
| 2005 | May 6 |
| 2006 | Apr 9 |
| 2007 | Apr 21 |
| 2009 | Apr 14 |
| 2011 | Apr 21 |
| 2012 | Apr 12 |
| 2013 | Apr 23 |
| 2014 | Apr 18 |
| 2015 | Apr 23 |
| 2016 | Apr 12 |
| 2017 | Apr 10 |
| 2018 | Apr 29 |
| 2019 | Apr 16 |
| 2020 | May 9 |
| 2021 | Apr 22 |
| 2022 | Apr 19 |
| 2023 | Apr 26 |
| 2024 | Apr 25 |
| 2025 | Apr 13 |
| 2026 | Apr 8 |
Each year's frost-free daysLong-term trend
See the data as a table
| Year | Frost-free days |
|---|---|
| 1974 | 159 |
| 1975 | 194 |
| 1976 | 187 |
| 1977 | 186 |
| 1978 | 158 |
| 1979 | 184 |
| 1980 | 171 |
| 1981 | 143 |
| 1982 | 182 |
| 1983 | 157 |
| 1984 | 160 |
| 1985 | 174 |
| 1986 | 164 |
| 1988 | 164 |
| 1989 | 140 |
| 1990 | 183 |
| 1991 | 167 |
| 1992 | 142 |
| 1993 | 160 |
| 1994 | 185 |
| 1995 | 142 |
| 1997 | 178 |
| 1998 | 187 |
| 1999 | 202 |
| 2000 | 176 |
| 2001 | 162 |
| 2002 | 169 |
| 2003 | 160 |
| 2004 | 184 |
| 2005 | 191 |
| 2006 | 185 |
| 2011 | 202 |
| 2012 | 177 |
| 2013 | 181 |
| 2014 | 197 |
| 2015 | 177 |
| 2016 | 213 |
| 2017 | 211 |
| 2018 | 169 |
| 2019 | 179 |
| 2020 | 159 |
| 2021 | 193 |
| 2022 | 172 |
| 2023 | 186 |
| 2024 | 174 |
| 2025 | 194 |
Each year's average temperature, April to SeptemberLong-term trend
See the data as a table
| Year | Growing-season temperature |
|---|---|
| 1973 | 18.9 °C |
| 1974 | 18.1 °C |
| 1975 | 18.3 °C |
| 1976 | 18.4 °C |
| 1977 | 20.3 °C |
| 1978 | 18.6 °C |
| 1979 | 17.9 °C |
| 1980 | 18.8 °C |
| 1981 | 18.2 °C |
| 1982 | 17.9 °C |
| 1983 | 18.7 °C |
| 1984 | 17.9 °C |
| 1985 | 18.6 °C |
| 1986 | 18.6 °C |
| 1987 | 19.7 °C |
| 1988 | 20.2 °C |
| 1989 | 17.8 °C |
| 1990 | 17.9 °C |
| 1991 | 19.6 °C |
| 1992 | 17.1 °C |
| 1993 | 18.4 °C |
| 1994 | 18.2 °C |
| 1995 | 19.1 °C |
| 1996 | 18.1 °C |
| 1997 | 17.3 °C |
| 1998 | 19.8 °C |
| 1999 | 19.6 °C |
| 2000 | 18.9 °C |
| 2001 | 19.1 °C |
| 2002 | 19.1 °C |
| 2003 | 18.5 °C |
| 2004 | 18.7 °C |
| 2005 | 20.2 °C |
| 2006 | 19.2 °C |
| 2011 | 19.0 °C |
| 2012 | 20.0 °C |
| 2013 | 18.7 °C |
| 2014 | 18.2 °C |
| 2015 | 19.2 °C |
| 2016 | 19.5 °C |
| 2017 | 19.1 °C |
| 2018 | 19.9 °C |
| 2019 | 19.3 °C |
| 2020 | 18.9 °C |
| 2021 | 19.8 °C |
| 2022 | 19.1 °C |
| 2023 | 18.9 °C |
| 2024 | 19.6 °C |
| 2025 | 19.4 °C |
| 2026 | 19.9 °C |
What this means for you: Since 1974, Herscher's last spring frost has stayed at about the same time of year. The frost-free season has grown by about 4 days per decade. Year-to-year swings are large, so keep using the safe date rather than the trend.
Source: daily records from Kankakee Wwtp (NOAA GHCN-Daily). Years with too many missing days are left out.