You can use Osmocote for your garden soil, trees, shrubs and perennials. Most plants suffer from lack of nitrogen, and your soil is not unusual in being low in nitrogen. Adding compost will help but to really boost the nitrogen consider adding steer manure, chicken manure or if you can get it, rabbit manure. You can even skip the rabbit and just add alfalfa pellets (rabbit food) to your soil for a quick fix of nitrogen. Feed stores sell alfalfa meal in large bags. Most trees and shrubs do not need annual fertilizer once they are established if they look healthy. If you feed too much there will be excessive growth that invites insect and disease problems. Perennials, roses and annuals all need more fertilizer than trees and shrubs, but once you improve your soil with compost and manure, the plants will typically need less fertilizer each spring. Plants in pots and annuals will always need fertilizer each spring. Keep growing, Marianne Binetti