Mosquito season in Benton County, IA: when it starts and ends
Mosquito months in Benton County
In a normal year mosquito season in Benton County, IA starts around April 25 and ends around October 12, about 24 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Benton County, and when
- Start tipping out standing water weekly by April 11.
- Book any yard treatment for late April, ahead of the July peak.
- Repellent can go away after October 12.
- No West Nile cases since 2016, so bites in Benton County are a nuisance; check window screens.
Benton County against the rest of IA
Benton County has the 85th longest season of 99 IA counties, at 170 days against 198 in Des Moines County and 160 in Worth County. Its mean temperature is 46.3°F.
- Dickinson County: April 24 to October 13 (172 days, 1 WNV)
- Hamilton County: April 24 to October 12 (171 days, 0 WNV)
- Lyon County: April 25 to October 12 (170 days, 19 WNV)
- Kossuth County: April 26 to October 12 (170 days, 3 WNV)
West Nile in Benton County
From 1999 to 2025, CDC ArboNET counted 3 human West Nile cases in Benton County (2 neuroinvasive) across 2 years. The worst was 2002 with 2; the latest was 2003.
See how the dates are worked out, and when mosquitoes go away for the winter.