Before hiking the AT in Maine in June/July we soaked everything except our underware in permetherine. Including our tent, rain gear, hats, bandanas. I used the strong stuff from the hardware store.

It worked well against mosquitos.

We had little trouble, although we met others who were badly harassed by them; they were visibly in clouds of mosquitos while we were left alone. Others had to wear long sleeved shirts and pants, while we walked most days in shorts.