Ido not worry much about insects in my home garden and am always concerned when friends ask me to review proposals that include general spraying of trees and shrubs for insects.
Practice integrated pest management in your garden to reduce the need for pesticides. I have only applied an insecticide once over decades of gardening at home. It was to control viburnum leaf beetle, which would have killed all of my arrowwood viburnums. I should have treated for azalea sawfly, which ended up killing all of my Northern Lights azaleas. I will not plant them again because I do not want to deal with the insect pest.
Begin by choosing the proper plant for your site and using good planting practices such as amending the soil with compost and planting at the proper depth. When possible, select plants