Outside is going to be a challenge, here ladybugs was the best thing I have done. They are everywhere this year. For me I have more problems with bugs inside.
What about h2o2 and water, I have used that to kill gnat larva in the soil.
IDK your area, but if you can remove under growth these blasted bugs nest on/in and burn it. Maybe a black ground cover over the area with the sun on it would kill them in the soil.