Mulch Volcanoes

The quickest and least expensive way to clean up your property is to mulch the beds. Even if you don’t have any plants in them. It will give you a fresh and tidy look for your property and is something you can do yourself. However, if the beds DO have plants, make sure you know how to mulch around them properly. It can be a massive drain of time and money to fix improperly mulched plantings and if you can’t fix them you end up replacing them.

I see what we call, “mulch volcanoes,” way too often around trees and shrubs. That’s what we say when we see a pile of mulch around a tree trunk. I also see those plants declining after just one season of suffocation. This may seem dramatic, but piling mulch around the trunks of trees and shrubs WILL kill them. Roots need air and if the plant can’t get enough, it will send out adventitious roots to find them. If you can’t see a root flare, the plant won’t be able to breathe. Girdling roots start to form, wrapping their way around the trunk in a confused effort to find air. As the trunk of the tree or shrub grows and expands outward, these girdling roots press on the trunk and literally strangle it.

To prevent this from happening, make sure you mulch properly. You want to see a root flare out at the base of the trunk(s) like a bell bottomed jean (see pictures below). You DON’T want to see a mound of mulch. If you see a mound of mulch, it may not be too late. Pull the mulch away and dig out your tree or shrub. If it is truly planted too low you can try to transplant it higher when the time is right for that plant. Or you can dish out around it but remember you will essentially be creating a little sump area where the water will pool. If the girdling roots haven’t fused to the trunk you can remove them with pruning shears. This will most likely shock the plant but with some TLC it may come back.

I have seen it in my own yard. An azalea my mom planted 20 years ago had slowly sunk into the soil and years of mulching around it had buried it about 8 inches up the trunk. I thought it was dying because it was old and decrepit until I started poking around the base. I dug it out two years ago, transplanted it and cut it back to rejuvenate the shape. It now looks healthy and happy.

Feel free to ask me any questions or send me pictures if you think your plants are in trouble from the dreaded mulch volcanoes. Good luck!