Mosquito season in Boone County, IN: when it starts and ends
Mosquito months in Boone County
In a normal year mosquito season in Boone County, IN starts around April 10 and ends around October 26, about 28 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Boone County, and when
- Start tipping out standing water weekly by March 27.
- Book any yard treatment for early April, ahead of the July peak.
- Repellent can go away after October 26.
- 1 West Nile case since 2016 (last 2025): you should use repellent at dusk June to August, more so if over 60.
Boone County against the rest of IN
Boone County has the 40th longest season of 92 IN counties, at 199 days against 231 in Floyd County and 177 in Steuben County. Its mean temperature is 51.7°F.
- Hendricks County: April 9 to October 27 (201 days, 1 WNV)
- Madison County: April 9 to October 27 (201 days, 2 WNV)
- Union County: April 10 to October 26 (199 days, 0 WNV)
- Carroll County: April 11 to October 26 (198 days, 0 WNV)
West Nile in Boone County
From 1999 to 2025, CDC ArboNET counted 3 human West Nile cases in Boone County (2 neuroinvasive) across 3 years. The worst was 2025 with 1; the latest was 2025.
Background: when mosquitoes go away for the winter; how the dates are worked out.