How Important Is It To Mulch?

There is no question, tree mulch is a stunning addition to any landscape and helps give your lawn a neat and tidy look.

But did you know mulch is more than just a pretty face? Turns out, your trees may actually need mulch to grow and flourish.

Why Do My Trees Need Mulch?

Your trees need mulch as a source of rich nutrients to grow healthy and strong. Trees in a forest are accustomed to using their roots to reach out and take in their food sources from all the organic material there is to choose from. Trees in our lawns never get that opportunity. Not only do they end up stifled by man-made surroundings, but they have to fight with other equally deprived plants and trees for the limited resources. Compaction of the soil surrounding the tree can also present issues that keep your trees from prospering.

Mulch also provides the soil with insulation against fluctuating temperatures, holds in water to provide moisture to the roots, prevents weed growth, and provides a buffer to reduce damage from lawnmowers.

What Kind of Mulch Should I Use?

Understanding the purpose of your mulch may help you decide what kind you need. Of the many varieties of mulch, they typically fall into two categories: organic and inorganic.

Organic Tree Mulch

Organic mulch is made of a variety of natural sources such as straw, wood chips, bark, pine needles, or paper. The mulch breaks down, supplying the soil with nutrients and generally leaving it better off than it was without any mulch at all.

When selecting organic mulch for your trees, it may be beneficial to understand your soil conditions and the needs of your trees. Commercial mulches can contain materials that may offer specific benefits to your trees.

Inorganic Tree Mulch

Inorganic mulch can be made of crushed stone, recycled tires, or landscape fabric. Even though inorganic mulch won’t break down, it has its uses—around your trees just isn’t one of them. In fact, placing inorganic mulch around your trees may be more harmful than beneficial.

Can I Make My Own Tree Mulch?

For an economical option, grass clippings, leaves, and sawdust may serve as mulch around your trees. You can either collect these items from your own landscaping projects or purchase them inexpensively from a tree care business. Landscaping materials that are not commercially produced may introduce weeds and chemicals to the soil around your tree. To prevent this from occurring, landscape materials should be composted before being used as mulch.

How do I Apply Mulch?

First, you will need to determine the area around each tree that needs to be covered in mulch. Typically, a three- to ten-foot circumference is adequate to cover the roots of the tree, but there are a couple of rules of thumb you can use to determine the exact size:

  • Use the dripline as a guide. The dripline is the outer edge of the canopy. The circle on the ground that corresponds to the drip line is the tree’s critical root zone.
  • On small trees, measure the trunk in inches, multiply by 1.5, and use this number, in feet, to represent the tree’s critical root zone.

Next, remove grass from the area where you will be applying mulch.

Add mulch to the depth of two to four inches within your dripline circle. If enough mulch is not applied, it won’t hold in moisture and insulate the soil from changes in temperature. Too much mulch may harbor excessive moisture and promote the growth of bacteria or fungi.

Apply mulch to within about four inches of the trunk of the tree. If mulch touches the base of the tree, it can stifle the bark’s ability to breathe and lead to rotting of the trunk and roots.

What If My Tree Still Isn’t Getting Enough Water?

If you find your tree is still dry and you have applied the adequate amount of mulch to retain water, try adding a ring of additional mulch about halfway between the mulch perimeter and the trunk to hold in water and direct it to the center of the tree. Take care that you don’t have standing water against the trunk of the tree.

Do I Need to Reapply Mulch?

You will want to add more mulch if some washes away in heavy rains, and over time as the organic materials break down. Just return it to its original depth of two to four inches.

As your tree grows and the dripline expands, you will want to increase your area of mulch surrounding the tree.
Mulch can provide aesthetic appeal to your landscape as well as many nutritional benefits to keep your trees healthy, strong, and beautiful all season long.

To learn more about how to best care for your trees, contact us at Front Range Arborists. We offer a full range of arborist services to assist you with all your tree and landscaping needs.


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