Q: How can someone know which combination of fertilizer numbers is right for each shrub, perennial, ground cover or annuals? Is there a list?
A: Despite the plethora of tomato fertilizers, azalea fertilizers, lawn fertilizers, orchid fertilizers, citrus fertilizers, etc, etc, etc, feeding plants is not so complex. Plant food requirements are pretty basic. They simply need nitrogen, phosphorus, potassium, calcium and magnesium, plus a few micro-nutrients that your soil probably already contains.
In general, plants are “grazers”. They absorb what they need from the soil. Your job is to insure that there is at least a little of each of the nutrients listed above present when a plant is growing.
As far as a list goes, I apply 10-10-10 to my garden and landscape plants in spring and in summer, turf fertilizer to my lawn three times per year and water-soluble houseplant fertilizer to my houseplants as needed. Those three products have satisfied my plants for years.