Fertilizing dogwoods correctly can be difficult. Different stages in the tree's life require different amounts of fertilizer. Overfertilization can kill young trees and reduce flowering in mature trees. If you fertilize too late in the year, tender new growth will not survive the winter.
Rake mulch from under the tree. The fertilizer must make contact with the soil.
Sprinkle 1 tbsp. of 12-4-8 or 16-4-8 fertilizer around dogwoods 12 to 24 inches tall. Apply the fertilizer 1 to 2 feet from the trunk.
Sprinkle 4 tbsp., or 1/4 cup, of fertilizer around dogwoods between 24 inches and 6 feet tall. Apply the fertilizer 2 to 3 feet from the trunk.
Sprinkle 1/2 lb., or 1 cup, of fertilizer for every inch of trunk diameter for dogwoods that are taller than 6 feet but have not reached their mature height. Measure trunk diameter 4 feet above the ground. Apply the fertilizer 4 feet from the trunk to 3 or 4 feet past the drip line (where the tips of the branches end).
Sprinkle 1/4 lb., or 1/2 cup, of fertilizer for every inch of trunk diameter for mature dogwoods. Measure trunk diameter and apply the fertilizer as you would in Step 5.
Reapply the mulch around your tree.