Trees in the forest benefit from the nutrients of their own leaves decomposing naturally into the soil. Their leaves are not raked, and they are not impacted by turf, pavement, or buildings. In contrast, trees located in urban environments are negatively impacted by man-made changes to the landscape such as new construction, irrigation, or pollution. This reason alone is enough to recommend deep root fertilization for all trees in urban settings.
A sound plant health care program begins with keeping the tree healthy. Annual
deep root fertilization with slow release, non-leaching fertilizer is the
first step in accomplishing this goal. It is important to point out that deep
root fertilization is not a cure for years of neglect, although it may be
of some help. For this reason, it is a good idea to protect your investment
by starting deep root fertilization earlier rather than later.