Tree Care & Preservation for New Hanover, Pender, Brunswick & Onslow Counties

tree fertilization wilmington nc

Tree Fertilization: Why, When and How

If you’ve spent any time in a forest lately, you have seen plant life thriving and growing on its own.

So why would your trees and shrubs need any kind of fertilization?

Trees that exist in a natural setting, such as a forest, receive nutrients from the vegetation and decaying matter around them. The soil is rich in nitrogen, phosphorus, potassium, and other nutrients from years of decomposing organic material. The entire ecosystem of a forest works together to provide everything trees and shrubs need to thrive.

By contrast, the soil in urban and suburban settings has often been stripped of nutrients and organic matter by typical landscape practices, such as blowing and removing fallen leaves, bagging grass clippings, and applying synthetic fertilizers and herbicides.

To replace those missing nutrients, we must apply fertilizer (or return the landscape to a more natural condition in which nutrients and organic matter are present in greater quantities).

With the right fertilization, your trees can look better, grow more strongly, and be more resistant to insects and diseases.

How to Fertilize a Tree

Fertilizer applied to the surface of the ground is typically absorbed by grass and weeds, and rainwater or irrigation can wash away many nutrients from granular, surface-applied fertilizers. So, while applying fertilizer to the ground may be helpful for shallow-rooted plants and turf grass, it doesn’t help trees or shrubs whose roots are much farther below ground.

For that reason, we prefer to use deep root fertilization when treating trees and shrubs.

What is deep root fertilization?

Deep root fertilization is a process in which fertilizer is applied through sub-surface liquid injection about 12 to 18 inches deep in the soil, or via trunk injection, so it can be easily taken up by the roots. From there, the nutrients make their way throughout the tree.

As an added benefit, slow release nitrogen fertilizer applied directly to the root zone does not run off into water systems.

Signs That Your Tree Needs Fertilizer

Not every tree needs fertilization, nor do all trees need it at the same frequency. But there are signs that indicate when a tree may be suffering from lack of nutrients and should be fertilized. These signs include:

  • dropping leaves earlier than usual,
  • smaller-than-normal leaves,
  • poorly colored leaves (turning light green or yellow),
  • a thin canopy,
  • several dead branches, or
  • stunted growth.

Sometimes those are signs of other issues, though, so a professional should help you determine the cause before fertilization is applied.

When Should Trees Be Fertilized?

Spring and fall are the best times for fertilizing trees. Depending on the situation, your trees might need fertilization twice a year to treat or prevent diseases. Young trees and shrubs need fertilization more often than large, mature trees, but if any of your trees are showing signs of distress, a fertilizer application might be needed.

Fall fertilization ensures that the trees and shrubs in your landscape have enough nutrients to sustain them through the winter months when many types of plants go dormant. Spring fertilization promotes healthy plant growth. Specialty fertilizers can be applied any time of the year if trees are in distress.

In Summary …

If you think your trees or shrubs might need to be fertilized, contact us today to set up a consultation. We’ll inspect your trees for any nutrient-related issues and, if needed, develop a customized fertilization plan for your yard.