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Expert Guide On How To Mulch Around Trees

In the forest, trees sink their roots into the soil that is enriched with microbes, organic matter, and vital nutrients.

As leaves fall from the trees, they decompose and replenish the soil creating a rich and well-aerated base ideal for root growth.

This isn’t the case in a typical yard. In a yard, soils are usually short on organic matter, nutrient-depleted, and subject to extreme temperature and moisture changes. Thankfully, you can remedy this using mulch.

By carefully applying mulch around your trees, you can raise the nutrient levels, so the trees grow healthy and beautiful. Confused about how to go about it?  Here are expert tips on how to mulch around trees:

Why should you mulch around trees?

Before we go into details on how to mulch around trees, let’s first look at the benefits that come with applying mulch:

Trees grow faster

According to a 2016 study by the United States forest service, mulching increases the growth rate of walnut trees by up to 89%.

Other fine hardwood trees such as maple, birch, hickory, cherry trees, and beech have been shown to grow 79% more with mulch.

Mulch reduces weeds growing around trees by up to 80%

By reducing the amount of light weeds receive, mulch prevents weeds from germinating. The mulch that does a good job at this is coarser organic much.

This HortTechnology study showed that mulch can reduce weed growth by 45% in the first year and 85% in the second year.

Mulch adds nutrients to the soil.

As mentioned above, soil in a typical yard isn’t as rich as the one you will find in the forest, so by adding mulch to it, you add more nutrients to it. Some of the nutrients you add to the soil include: potassium, nitrogen, and phosphorus.

Although, the more the mulch you add, the more the nutrients you add into the soil, adding too much mulch can be harmful to the trees, so be cautious how much you add. For best results, add 2-3 inches.

Mulch reduces water evaporation by 35% and soil erosion by 86%

Studies show you can reduce water evaporation by as much as 35% when you apply organic mulch. Adding the right amount of mulch also reduces the frequency you water your trees as the base remains moist for a long time.

According to Washington State University, adding a layer of mulch can reduce soil erosion in your yard by up to 86%.

Mulch keeps tree roots at the right temperature.

Since you are adding layer around your tree roots, mulch functions as a constant insulator for your tree by keeping the soil warm in winter and cool in summer.

For best results, use organic, coarser mulch as it does a better job than inorganic or processed mulches such as fabrics or plastics.

How to mulch around a tree

Although mulching is vital for your tree’s growth, it’s not hard to succeed with it. Simply follow a series of steps, and you will give your trees the royal treatment they deserve. To help you out, here are tips on how to go about it.

It’s wise to apply mulch before summer heat kicks in, but you can apply mulch at any time of the year. If you live in the colder regions, wait until the soil warms in spring before applying it.

Apply mulch in a ring extending outward from the trunk at least 3-6 feet. Some homeowners apply mulch to the tree’s drip line (the edge of the outmost leaves), and there is no harm in doing so as roots tend to extend beyond that point.

It’s still okay to apply mulch inside the drip line, especially if you have large, mature trees.

When making the application, take caution you don’t pile mulch directly against the tree trunk. Pull it back a few inches from the trunk, creating a doughnut-hole effect that allows air to reach the trunk.

A good rule of thumb is to apply mulch 2-3 inches deep. If you got sandy, fast-draining soils, apply a deep layer that is at least 4 inches deep.

Does your soil drain slowly? You should apply a 1-2 inch layer.

The frequency at which you mulch your trees depends on your mulch. Organic mulches such as pine straw, ground bark, wood chips, compost, and cottonseed hulls break down fast, so you need to replenish them more frequently.

Inspect your mulch at least once a year or twice a year if you live in warmer climates. Before piling the mulch, check the existing depth and refresh it if necessary.

If you live in cold climates, refresh mulch after the ground has frozen. This is to provide some winter protection, especially if you recently planted new trees.

Before applying mulch, remember to remove any existing turf or weeds.

Tree mulching best practices

To get the most from mulching your trees, you need to do it right. Here are tree mulching best practices you should consider:

Don’t build mulch volcanoes

Trees need oxygen, water, light, and nutrients to grow and thrive. Unfortunately, homeowners pile so much mulch around their trees, which deprive the roots of air, water, and provide a haven for pests and diseases.

When applying mulch to your trees, avoid volcanoes at all costs. As mentioned above, a good rule of thumb is to apply 2-3 inches of mulch to your lawn.

Ensure mulch spreads to the drip line to protect the trunk from mower and trimmer damage and, at the same time, prevent your tree from competing with your lawn for moisture and nutrients.

Avoid thick layers

As much as you might have the impression that applying a lot of mulch will provide more nutrients and protection to your trees, you should avoid it as it causes more harm than good.

The thickness of mulch you apply around your tree depends on the type of soil and mulch.

Got river rock, gravel, stones, lava rock, or sawdust type of mulch? Apply a one-inch layer around your yard.

Grass clippings and compost provide the best results when you apply them in one to two inches.

Wood chips perform the best when you apply them in layers from one to three inches thick, while pine needles, shredded leaves, and bark perform the best when you apply it in two to three inches thick.

Apply the right mulch

You should know that all mulch isn’t the same, and some will do best around certain trees than others. Three of the most popular tree mulches are wood chips, bark mulch, and shredded leaves.

Research and find the best ones for your trees. The mulch you use should also match the theme of your yard.

Avoid dirty mulch

The best mulch to use is a pest-free mulch that isn’t stinking. Stay away from any mulch with a chemical smell. Also, avoid mulch teeming with ants and other insects.

As you should avoid dirty mulch, you also should stay away from old mulch. In addition to the mulch risking spreading diseases to your trees, it also might not be having the necessary nutrients; hence it won’t provide you with the benefits you are looking for.

On my 15th birthday, I became the designated gardener in my home.

Now at 32, I have a small garden and every day I'm out trying different plants and seeing how they grow. I grow guavas, peaches, onions, and many others. Want to know more about me? Read it here.

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