If your lawn care company has tree and shrub service offerings, this blog post is for you. Whether applying fertilizers or pesticides, you have several application methods to choose from. The decision will depend first on the product label, but there are other factors to consider if your product allows multiple application methods. Keep reading to learn more about six common methods for applying products to trees and shrubs. 


The first method is granular, where you apply granules to the base of the plant. As the product is watered in with irrigation or rainfall, the granules dissolve into the soil for the plant to absorb. The tree or shrub absorbs the product through its feeder roots, which typically grow in the top four inches of soil. A granular fertilizer like ATS 14-14-10 provides excellent results for trees and shrubs.


Another familiar method is foliar, which uses a sprayer to apply liquid products to leaves. This method works with a backpack sprayer for shrubs and small trees or a larger sprayer for trees that have foliage out of reach. Foliar application is a popular way to deliver insecticides and fungicides because they go directly to the leaves and produce quicker results. This method is also effective for short-term nutrient application, such as with Foliar-Pak Chloroburst L to reduce chlorosis.

Basal Bark

Basal bark application involves spraying the base of a tree or shrub with a liquid solution using a sprayer with a cone nozzle on low pressure. The solution then seeps through the bark into the tree system. This method is commonly used to control emerald ash borers, and it works best on trees or shrubs with thin bark. It’s important to add a crop oil to your application to help it penetrate the bark. 

Root Drench

Root drench applications involve pouring your liquid solution around the base of the plant and allowing it to seep into the soil. It’s important to drench the area as wide as the feeder roots are, which will depend on the type of tree or shrub you’re treating. This method is effective for season-long insect control with imidacloprid. It also works well to apply fungicides for soil-borne pathogens, which foliar applications can’t control. 

Deep Root Injection

Deep root injection is similar to the root drench method but with a different application process. Deep root injection uses a high-pressure hose attachment to inject a liquid solution directly into the rootzone throughout the dripline. This method works with many products, including fertilizers, fungicides, and insecticides.

Tree Injection

Another injection method is tree injection, which involves drilling a hole into the base of a tree and inserting chemicals into the hole through a refillable port. This method became popular for controlling emerald ash borer, but it’s also an effective way to correct some micronutrient deficiencies. Once the treatment is complete, the tree will heal the hole naturally. You can learn more about the tree injection system we carry here

Product labels are a good place to start for determining which application method you can use. Some products list rates for multiple application methods, in which case you can choose the one that works best for you.