Tree feeding--or fertilizing--involves the right diet for the right tree at the right time.  Benefits can include faster rate of growth, larger and greener leaves, the correction of nutritional deficiencies, and a speedier recovery from diseases (such as verticillium wilt).

But feeding may not be a favor for your trees.  Increased rate of growth may be good for young saplings, but more mature trees may be left with weaker wood, and therefore more susceptible to damage from storms and more in need of pruning.  The lovely larger leaves can become more subject to disease.  And some trees by nature grow slowly.  Check on what to expect from your variety before you buy it.

Inspect conditions at the site: are tree needs on soil texture, drainage, and exposure right?  Root and trunk restrictions (such as rocks or a girdling root) or damage from disease and insects may be the "slow-grow" culprits.

Trees have evolved systems that enable them to function and grow well in soils considered nutritionally poor by most U.S. Department of Agriculture standards.  Fertilization bypasses these systems and can be unnecessary--even harmful--to the plant.

Consult with your local arborist or county extension office when you're trying to pinpoint your tree's condition.  Deep injections aren't necessary because most of the tree's feeder roots (the ones using the nutrients) are in the top ten to 12 inches of soil.

Fertilizer broadcast on the surface works as well as a soil injection.  Place plant food where the roots are--under the crown spread of the tree and a few feet beyond.

Except where specific minerals are deficient, most trees show little response to anything but nitrogen.  Don't use more than six pounds nitrogen per 1,000 square feet of surface.

Complete fertilizers (those also containing phosphorus and potassium) in quantities sufficient to supply six pounds of nitrogen per 1,000 square feet are sure to injure grass near the tree if applied on the surface.