Integrated Pest Management (IPM) was introduced by the USDA in 1950 to address crop damage.  The program consists of 4 progressive stages of PHC management from least impactful to most impactful.

Categories Examples
Mechanical Physically removing bag worms. Washing off thrips. Fly paper.
Cultural Relocating a dogwood tree out of direct sunlight or a shrub from rainspout discharge.
Biological Green Lacewing for hard-shell scale and aphids.
Chemical Least preferred because of collateral damage to environment and plants themselves.

What do I need to do differently?

You may already be addressing many of the categories, like physically removing bag worms or using an Air Knife.  You may need to re-orient your thinking by not automatically choosing the chemical approach first if there is an option that has less negative impact.  besides, the chemical option is often more expensive than other options.  You can add new treatment choices gradually, as you learn about them and feel comfortable offering them to your customers.

Where can I learn about this more comprehensive approach to PHC?

21st Century IPM is your go-to resource for everything you need