Fertilizing in the Fall
In the natural setting, a tree would have plenty of space for its roots to spread out, the leaves would remain on the ground to provide future mulch and keep its roots cool and moist, and it would have plenty of room for its branches and stems to stretch out to the sun. In most of our residential settings, a tree must compete for water and nutrients with the grass, any shrubs or flowers, and it usually must adapt to a tighter place for its roots and branches to survive, let alone thrive.
We work to help your tree not only survive, but thrive by fertilizing it in late fall/early winter. Even though your tree appears to be dormant (it has lost its leaves), under the grass, the roots remain active, growing and storing food in anticipation of the tree's new growth next spring. Our fertilizing program consists of a subsurface fertilization that takes the product directly to the roots. We inject our water-soluble fertilizer 12"-18" down into the ground around your tree and out to where the roots are working. The roots of your tree have available to them a well-balanced, low-salt, low-nitrogen fertilizer that is taken up and either used right away or stored for future use in the spring. Our fertilizer consists of the macronutrients nitrogen, phosphoric acid, and potash; and the micronutrients copper, iron, manganese, and zinc.
Most trees in the residential setting are not able to produce enough food and energy to support new and existing growth at maturity because of the limited space the roots have to grow. The roots spread out much farther than the dripline of the canopy of a tree. To estimate how far the root system of a tree reaches, estimate the height of the tree and multiply by 3. That will give you the total diameter of the root system of the tree.
For example, if you have a mature maple that is 80' in height, its root system will have a diameter of 240'. From the base of the tree, the roots stretch out 120' in all directions–in an ideal growing area. The tree's outermost roots are the ones that do the majority of the work, too, taking in water and nutrients from the soil.
If you have a yard with mature trees, not only do those trees' roots share the area available to them, more than likely they are not able to stretch out to their full capacity. This is why fertilizing your trees on a yearly basis is a wise decision. Fertilizing is always a good idea. It helps the tree by providing needed nutrients, which in turn, provides the tree with energy to promote good, overall health. And it helps the tree in resisting damaging insects and disease. The more energy the tree has available to it, the more it will be able to fend off any insects or disease.
A good fertilizing program will help your tree to thrive. And if the tree is healthy, it will provide many years of beauty, shade, and worth to every residence.