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The Importance of Using Mulch to Protect Tree Landscaping in Denver

July 12, 2017

Tree trimming and pest management is crucial, but mulch is another one of the most important components of tree landscaping in Denver. Unfortunately, it’s often overlooked by people who don’t understand the many ways that mulch benefits their trees. Why should you apply mulch around your trees? How should you apply it? Here’s what you need to know about using mulch to protect the trees in your yard:

Acts as Insulation

Tree roots are sensitive to temperature changes, and may begin to die off if they are exposed to extremely cold or hot temperatures. However, mulch acts as insulation and protects your tree roots from experiencing fluctuating temperatures. A fresh layer of mulch will keep the soil around your tree’s roots warmer in the winter and cooler in the summer, thus keeping the tree roots healthy and thriving.

Conserves Moisture

Tree roots need water to survive, however they may not be getting enough water if you don’t already have mulch in your yard. Why? Soil heats up when temperatures begin to rise in the summer. At a certain point, temperatures will be high enough to cause evaporation, which means the soil will start to lose its moisture and tree roots won’t get the water that they need to survive. This can be prevented by applying a layer of mulch on top of the soil. The mulch will prevent sunlight from reaching the soil and thus drastically slow down evaporation so the tree roots have more time to absorb moisture before it’s gone.

Lawnmower Protection

If tree roots are exposed or near the surface of the soil, they can easily be damaged by a lawnmower’s blades. Whoever mows your lawn should know that areas with mulch do not need to be mowed, so applying a layer of mulch around your trees should be enough to prevent this problem. But, even if the person who mows your lawn does go over the area, mulch adds another layer of protection and prevents the blades from reaching the roots.

Soil Erosion

Without mulch, soil may begin to erode during a heavy rainstorm. The water can cause the layer of topsoil to break apart and slowly disperse. Since the topsoil contains organic matter that is beneficial to your trees, you should take action to prevent soil erosion. Fortunately, it’s not difficult to do so. Simply apply a layer of mulch around your trees to keep the soil in place so your trees can continue to absorb nutrients.

Reduces Competition

Tree roots compete with other plant roots underground for the nutrients and moisture that they need to survive. If you have recently planted new trees in your yard, it’s imperative that you reduce competition to ensure that the new tree roots receive enough nutrients to grow. To do so, apply a layer of mulch around the base of the tree that is about four inches deep. This is enough to prevent weeds and other unwanted grasses from sprouting up around the tree and competing with its roots for nutrients.


Besides keeping trees healthy, mulch also improves the overall appearance of your tree landscaping. The right type of mulch can make your entire yard look neater, healthier, and more vibrant. In fact, real estate agents often advise sellers to put down a fresh layer of mulch before listing their homes to improve the curb appeal.

How to Apply Mulch Around Trees

As you can see, mulch plays an important role in keeping trees healthy and strong. But, it must be applied properly or your trees won’t reap these rewards. You may think that putting down a layer of mulch is simple, but it’s actually more complicated than it may appear.

First, choose the right type of mulch. There are several different types, but it’s recommended that you stick to hardwood bark, which comes in small or large chips. This type of mulch is safe, attractive, and long lasting, so it’s viewed as one of the best options. If you don’t choose hardwood, the very least you should do is make sure that the type you choose is organic. Organic mulches will break down and provide nutrients to the soil, but inorganic mulches won’t.  

One of the biggest mistakes that you can make with mulch is applying it in the shape of a mound around the base of your tree, so it starts very thick and then becomes thinner as you move further away from the tree. Mulch should not actually come in contact with the base of your tree or it will cause moisture to accumulate on the trunk, which leads to pest infestations. Instead, leave a distance of a few inches between the tree trunk and the mulch. Then, apply the mulch all the way out to the drip line of the branches. The mulch should never be more than four inches deep. Learn more about mulching trees and shrubs.

Once mulch has been applied, make sure you check it frequently to see if it needs to be replenished. Hardwood mulch should only need to be replaced a few times every year, so this isn’t shouldn’t be much of a hassle. You should also check to ensure the mulch has not become matted. If it has, take a rake and gently run it over the mulch, otherwise the roots may be deprived of water and other nutrients.

Many people only use mulch during certain times of the year, but it’s best to use it year-round. Therefore, if you ever remove old mulch from around your trees, be sure to replace it quickly so tree roots don’t have to adjust to new conditions.

For more tips on how to protect the trees in your yard, talk to the professionals. Arbor Garden is a locally owned and operated tree services company that specializes in tree pruning, removing, stump removal, planting, and pest management. Our team will be able to answer your questions and determine how we can help protect your trees. Contact us today to learn more about our services and receive a free estimate.