Fertilizing Trees and Shrubs

Q. Is it necessary to regularly fertilize my trees and shrubs? If so, how often should it be done?

A. Adequate soil fertility begins with good soil. Generally, trees and shrubs do not require synthetic fertilization unless a nutrient deficiency is observed. In addition, normal leaf color and size, as well as annual growth will also dictate whether or not fertilizer needs to be applied. Being familiar with normal plant growth is an important step to determine if the plant will benefit from additional fertilization. A two- to three-inch layer of compost such as leaf mulch or other organic matter can be applied in the spring and is helpful in resupplying the soil with necessary nutrients. Supplemental fertilization is best applied when plants are in their active growth cycle. The roots of trees and shrubs are able to absorb nutrients at any time of the year as long as the soil is not frozen.