Fall fertilization is vital for keeping trees vigorous and encouraging better growth. Despite its importance, many homeowners neglect to hire a professional to fertilize their trees and assume they can do it later. Yard trees can benefit from regular fertilization to replace the nutrients they take up from the soil.
In this article, we will examine the benefits of fall fertilization and provide a brief primer on the proper timing of the service. We’ll also give you some signs to watch out for to identify trees that can benefit from fall fertilization.
PRO TIP: Fertilization is just one part of Regal Tree’s tree preservation services to help keep trees thriving and reduce the need to remove mature trees.
Key Takeaways
- Fall fertilization helps trees build their roots during the dormant period of the winter and allows them to grow better during the next growing season.
- Fertilizing in the fall also improves the color of trees, leaving them more vigorous and better able to withstand insects and diseases.
- Fall fertilization should focus on replacing missing nutrients in the soil rather than just being a general application.
- Typical signs a tree may need fertilization include stunted growth, smaller leaves, and early fall colors.
- Be careful not to apply a high-nitrogen fertilizer in the fall, and time your application to after the first killing frost of the year.
Benefits of Fall Fertilization
Fall fertilization provides numerous benefits for your trees, including:
Helping Build Roots During the Winter
While the portion of the tree above ground won’t do any growing during the dormant season of the winter, a tree’s roots are another story. Tree roots continue to expand and grow in search of nutrients and water, even during the winter.
You can promote more root growth for a healthier tree by providing supplemental nutrients.
Better Growth the Next Season
Fall fertilization (much like planting a tree in the first place) is not for those who want instant gratification. You likely won’t see much difference in your tree after fertilizing it in the fall. The fundamental changes will come in the next year.
With the additional nutrients you provided, a tree will enter the spring with stored-up energy and use it to push out new growth.
Improved Tree Color
Whether you prefer how your trees look in the summer, fully leafed out and green, or with their fall colors, fertilization can help improve color. You’ll enjoy greener trees and fewer yellow leaves early in the growing season. And in the fall, your fertilized trees will display brilliant fall colors rather than just withering and dying.
A More Vigorous and Resilient Tree
You’re probably aware that a healthy person with a balanced diet of vitamins and minerals can better resist disease and illness than someone malnourished. The same principle applies to your trees as well.
Fertilization lowers the stress of a tree when it replaces depleted nutrients in the soil. Fall fertilization allows a tree to have time to absorb the nutrients throughout the dormant season and then enter the following summer with reduced stress and more vigor. With new concerns for our trees, like invasive insects, keeping your trees healthy and unstressed is crucial.
Replace the Nutrients Lost in the Summer
Trees will use the available resources in the soil to grow larger in the summer. In a forest, decomposing leaves and branches will add nutrients to the soil, allowing a tree to repeat the process in the following year. Trees in yards in urban environments do not have this same access to decomposing organic matter, as homeowners rake it up every fall. And urban and yard trees are often exposed to stressors forest trees don’t have to worry about.
Have an arborist conduct a soil test to determine if your soil lacks crucial nutrients for trees to grow. If so, fertilization is an excellent short-term solution to the nutrient deficiency. Homeowners should use fertilization in conjunction with soil-building techniques (like adding organic matter and compost to their soil) to create more naturally nutrient-rich soil.
A silver maple tree displaying the signs of chlorosis (the yellowing of leaves due to a lack of chlorophyll). Photo courtesy of William Jacobi, Colorado State University, Bugwood.org.
Signs Your Trees May Need Fertilization
While a soil test will give you a definitive answer to whether your tree needs fertilization, a tree will display several symptoms that could indicate a nutrient deficiency. Some common signs your trees need fertilization include:
- Smaller leaves: A tree lacking in nutrients will have difficulty growing leaves as large as expected. This can be difficult for a layperson to see, and we recommend comparing the size of leaves to try and determine when they are growing smaller.
- Stunted growth: Healthy trees should get bigger every year. When they don’t have the proper nutrients, they will use their limited energy to focus on maintenance rather than development. If you notice your tree did not get any larger in the summer, it may be pointing toward a tree with a nutrient deficiency.
- Discolored leaves: A tree’s leaves should be green throughout the summer. Premature fall colors are often a sign of something stressing your tree. This stress may come from a lack of nutrients, though other problems could be the culprit.
Young trees also require more fertilization than mature, established trees. Speak with an arborist about setting up a fertilization schedule when you plant a new tree.
WARNING: Fertilization should always be targeted to replace a nutrient deficiency in your trees. Applying general fertilizers or too much product can harm your trees and potentially kill them. Always have a professional conduct a soil test before using any fertilizer.
Concerns for Fall Tree Fertilization
While fertilization is essential to any Greater South Easton resident’s fall tree care checklist, caution is crucial to avoid doing more harm than good.
Avoid High-Nitrogen Fertilizers
Nitrogen is an essential macronutrient for trees and the primary growth catalyst. Using a high-nitrogen fertilizer in the fall will cause a tree to respond by generating new growth. These new branches will not have time to establish before the winter hits and will most likely die from the cold, causing stress for your tree.
A respectable tree care company will never suggest using a high-nitrogen fertilizer in the fall. Instead, they will suggest slow-release fertilizers that will provide nutrients slowly throughout the dormant period instead of delivering excessive amounts of nitrogen all at once.
Timing Your Fall Fertilization in Greater South Easton
Timing is everything when it comes to fall fertilization. Fertilizing too early may encourage new growth before the winter while applying it too late will lead to the nutrients not getting to the roots due to frozen ground. And even worse, shifting weather and climates may mean conventional wisdom no longer applies to timing your fertilization.
Generally speaking, you can safely apply fertilizer to your trees and shrubs after the first killing frost but before the ground freezes. If you aren’t sure about the timing, ask an arborist for recommendations based on your trees.
Schedule Your Fertilization with Regal Tree Today
Fertilization is vital to keeping your yard trees healthy and stress-free. Providing supplemental nutrients for your trees in the fall gives them a chance to jump-start in the next growing season. While beneficial,
fertilization is best left to professionals who understand a tree’s needs and will avoid making common fertilization mistakes.
At Regal Tree, we know the best way to get fertilizer to trees and how to give your trees the best chance at thriving in the coming year. Set up a fall fertilization schedule with us by calling 774-719-2450 or requesting a quote online.
