Its true that large, well-established and healthy trees may not need much supplemental feeding, but smaller trees and shrubs will pay you big dividends in return for your feeding investment during their first several years on your property. Your payback will include better disease and insect resistance, improved flowering, and much quicker establishment than similar plants denied regular fertilization.

The primary nutrients; nitrogen (N), phosphorus (P) and potassium (K)are all used by your trees in different ways.

Nitrogen encourages fast trunk and branch growth, and the production of healthy and dark green leaves.

Phosphorus stimulates vigorous root growth (which makes it especially beneficial to recently planted trees and shrubs). Phosphorus also promotes flower bud formation and increases resistance to cold.

And potassium makes the trees stronger, helping them to withstand wind and ice breakage as well as diseases.

Fertilizing trees should put the nutrients within reach of the feeder roots. This means feeding an area that reaches from about 1/3 of the distance from the tree trunk to the dripline (on the inside) to a spot about the same distance outside the dripline. Fertilizer needs to be placed into holes that are about 6 to 12" deep throughout the target area. For good distribution, you may need up to 10 feeding holes per inch of trunk diameter up 6 to 12" deep throughout the target area. (a tree 5" across may need 50 or so holes in the feeding zone). That's a lot of holes, but it assures that the fertilizer will be evenly available to the tree.

Trees can be fertilized anytime between when the sap goes down in fall or winter until about mid-July (at the latest). Feeding between July and fall stimulates late growth that gets no chance to harden off and is more susceptible to damage from winter cold and winds. Early spring is probably the ideal feeding time, but with slow release materials, any time during the window will give excellent results.