As a general rule, we recommend you use a balanced blend fertilizer such as 13-13-13.
Sprinkle a small handful around the base of the plant, but don't let it stay on the branches or leaves. Wash them immediately with water if contact is made. Water the plant thoroughly. A liquid fertilizer, used at the recommended concentration, also is a recommended fertilization method.
Spread the recommended dose around the base from the edge of the root ball out to the drip line of the canopy. Big trees will need more than smaller trees. Root feeders are an excellent way to fertilize and water trees.
Evergreens and Broadleaf Evergreens:
Evergreens and Broadleaf Evergreens...(e.g. yews, junipers, azaleas, & rhododendrons)... prefer a fertilizer such as Mir-AcidŽ brand fertilizer that will increase the acidity of the soil. Follow the manufacturer's directions for recommended rates.