Host: Gary Bachman, Ornamental Horticulture Specialist
Driving around town this I couldn’t believe my eyes but they were, mulch volcanoes today on Southern Gardening.
I have embarked on a mission to convince people that much volcanoes are bad for our trees. So who’s to blame? Most gardeners love their trees and want to do what they can to help them grow and prosper. Mulch reduces weeds, cools the soil, and conserves precious water in the tree’s root zone. The ideal mulch thickness is two to three inches, but some gardeners think 6” to 10” has to be better: and mulch volcanoes are born. When a thick layer of mulch is spread around the trunk of a tree many things can happen, and they’re all bad. The mulch will indeed hold moisture; but it will be up against the tree trunk creating a condition where the bark starts to decay. This allows fungi, bacteria, and insects to get under the bark and cause problems internally for the tree. Circling roots are another problem that is commonly found in mulch volcanoes. As the tree grows the circumference of the trunk grows larger eventually strangling the tree. The proper way to mulch a tree is to first spread an even layer around the base of the tree. I personally like big mulch beds around trees to ease lawn mowing and reduce edging. After the mulch is applied, use a rake or by hand pull the mulch back away from the tree trunk. Until next time, I’m horticulturist Gary Bachman enjoying our Southern Gardening