Considerations For Proper Mulching Of Trees

Mulch is truly the unsung hero of the garden. Most people think that the purpose of mulch is mostly for aesthetic appeal, but it has so many more functions than just that! Mulch can help to promote healthy soil in so many ways. It prevents erosion by keeping the soil underneath in place. It keeps weeds at bay by blocking the sunlight they need to thrive. It locks in moisture by preventing evaporation and shades the roots of your trees from the hot sun.

Organic Vs. Inorganic

Mulch is really just a term that is used for a material that is layed on top of the soil, and so it can be derived from a wide variety of materials. There are two main categories of mulch, these are: organic and inorganic.


Organic mulch is any compostable material that you can use to spread out on top of the soil in your garden. Most gardeners tend to use bark or wood chips for this purpose, but you can use anything from pine needles to leaves, or even lawn clippings.

One of the major benefits to organic mulch is that it will decompose over time. This process will restore the soil by putting nutrients back into the ground. The downside is that organic mulches will need periodic maintenance and will need to be replaced every few years.


Any material that cannot decompose is considered inorganic mulch. Gravel or small stones are commonly used as a material for mulch, but you may have even seen sheets of plastic or ground up rubber used for this purpose. 

Inorganic mulch is considered to be a more or less permanent installation. This is an advantage if you don’t want to do a lot of upkeep. Additionally, some people find multicolored rocks or river stones to be more aesthetically pleasing than bark or wood chips.

When To Lay Mulch

While your plants and trees will appreciate a good mulching any time of year, we think spring and fall are best. If you are using an organic mulch, laying it in the spring time can be beneficial as the coming rains will work to break down the organic materials in the mulch returning nutrients to the soil. If you live in a particularly cold climate, applying an extra layer of mulch in the fall is useful to provide extra insulation for your plants’ roots.

Tips For Applying Mulch

Gather Your Tools

When you’re preparing to apply mulch in your yard, you’ll first want to have all of the proper tools at hand. A few things you’ll likely need:

  • Wheelbarrow: This will make it easy to move your mulch around to different areas of your yard.
  • Pitchfork or shovel: These will be useful in moving your mulch in and out of the wheelbarrow.
  • Rake: A heavy duty leaf rake is acceptable for spreading mulch, but a bow rake is better. You’ll just need something that is sturdy enough to break up clumps of mulch, and the flat side of a bow rake ideal for smoothing out your mulch job.
  • Handheld spade: This is useful for applying mulch in tight or difficult spaces.
  • Gloves: Wear gloves to keep your hands clean and protect them while you work.

Make Sure You Have Enough Material

Before you begin mulching, you will want to calculate just how much you will need. There is nothing more frustrating than starting a project and not having enough materials to finish! Keep in mind that 1 cubic foot of mulch will cover about 6 square feet of area roughly 2 inches deep.

Clean Your Target Mulch Areas

Before spreading new mulch, you should take a little time to remove any debris from the area you plan to mulch. This includes fallen sticks or leaves as well as any leftover mulch from previous years. It’s a good idea to define the edging around the area where you will be spreading the mulch. You can use a shovel to cut a clean edge between your lawn and area to be mulched.

Apply Water

If you haven’t had much rain recently, it can be a good idea to give your trees or flower beds a good watering before laying down mulch. Applying mulch after a good watering can help to lock moisture into the soil. Water again after you lay the mulch. This is optional, but can help the mulch to settle into place.

Cover The Right Area

When you are applying mulch to trees you need to make sure you cover the appropriate area. You need to keep in mind how close to the trunk you should be mulching as well as how far away. Mulch should be kept away from the trunk and begin at the area where the roots flare out from the base of the tree. Avoid piling mulch up against the trunk as this can promote disease. Best practice dictates that you spread mulch all the way out to the edges of the tree’s canopy. This means that the area of mulch under the tree will increase as the tree grows older.

Don’t Over Mulch!

Applying too much mulch is a common mistake. In general, your mulch should be between 2-4 inches. Use less mulch if the soil underneath doesn’t drain well. If you are using a denser material such as river rocks, consider applying an even thinner layer. An inch deep would be sufficient to cover the area while still allowing oxygen to reach down to the roots.

Leave It To The Professionals

Mulch can provide so many benefits to your garden. A proper application of mulch can work wonders for your trees, protecting their roots from the elements and providing valuable nutrients. 

While we consider this to be a comprehensive guide to mulching, maybe you’ve decided that applying mulch is not for you. That’s ok, that’s why we’re here! If you would like to have your mulch installed by a tree care specialist call Kootenai Tree Service.