Think Twice Before Creating Mulch Volcanoes Around Your Trees. Here's Why

If you've ever seen a recently planted tree, you may have noticed mulch mounded up around it, and reaching a long ways up the trunk. You may have even done this yourself. After all, mulch is good for trees and plants, right? Unfortunately, as beneficial as mulch can be, this strategy of creating a "mulch volcano" can actually harm your trees and slowly cause damage.  

Believe it or not, you don't actually want mulch to be in contact with a significant section of the tree's trunk. This causes the bark to be constantly wet, which exposes the entire tree to be susceptible to disease and damage. The heat from the mulch breaking down can cause additional damage to the bark. 

Over time, this mulching strategy can also cause your tree to create additional roots which wrap around the trunk of the tree, causing further damage ... or even killing the tree. Stressed trees are also far more likely to face attacks and potential death from insects. So instead of needing to treat for pests like tree borers, you may be able to make your trees less vulnerable to them by using a better mulching method.

Just because mulch volcanos are a bad idea that can lead to damaged or even dead trees, that doesn't mean you want to stop mulching your trees entirely. Mulch still helps to regulate soil moisture and temperature and prevents weed growth, after all. You just need to use the right technique when mulching to avoid potential damage.

When you mulch around a tree, be sure not to apply it any thicker than 1 to 3 inches. This isn't a case where more is better. While using a lighter application of mulch may mean you have to reapply it more often, doing so is actually much better for the health of your tree. Additionally, you should avoid getting any mulch directly against the trunk of the tree. As an attractive alternative, you could also consider filling in the areas under a tree with a low-maintenance living mulch. This area can be a perfect spot for many ground cover plants.