Proper Mulching
Frequently Asked Questions
I thought tree roots go deep down – how can mulch hurt?
This graphic shows how tree roots spread. The feeder roots are found at and beyond the drip line (the area outside the canopy).
Can I remove the mulch volcano that is around my tree? Won’t that damage the tree at this point?
Should I not apply any mulch since it is bad for the tree?
Mulch can be beneficial for a tree. Research has shown that trees grown in a proper mulch bed will grow twice as fast and be twice as healthy as trees grown in grass. Grass sends out a chemical to kill tree roots, so placing a wide mulch bed around your tree will help the tree. Make sure the mulch is no deeper than 2-3 inches and at least 3-6 inches away from the flare of the tree. If possible, the mulch should go all the way out to the drip line of the tree, where the feeder roots of the tree are found. Here is a picture of a perfect mulch bed around a tree.
Do I need to remove the excess mulch from all my trees and bushes?
You are only required to remove the excess mulch from the city owned trees (those located between the sidewalk and the curb). Going forward you are required to reapply the mulch correctly. We encourage all residents to do the same for the trees and shrubs in your yard. Landscaping is a big investment and this will save you money in the long run because your trees and shrubs will live longer and be healthier.
Why is Tree Fredericksburg and the City so different?
I learned about photosynthesis in school – trees take in carbon dioxide and give off oxygen? What is this talk about trees taking in oxygen?
The flare is often referred to as the lungs of the tree. If the tree is planted too deep or mulch is pile up around the base of the tree, then the tree is not able to take in enough oxygen. We need to keep mulch completely off of the tree flare.
What happens to a tree deprived of oxygen?
Here are two pictures from the same neighborhood. Both are maples, and were planted at the same time. One had mulch piled up around the base and one did not. Can you guess which one had the mulch volcano?
What kind of mulch should I use – I like to apply fresh mulch so my beds look pretty?
Why do landscapers put so much mulch on my trees? Don’t they know the right way to do this?
The practice of over mulching is driven by a number of factors. Some thought it “pretty” and started to apply mulch this way. Others followed because they saw commercial landscapers applying mulch this way and thought it was the correct way. Many quality landscapers now know they are damaging the trees and shrubs but homeowners still insist on having it done this way because they see it done at commercial establishments.
What else should I know about trees?
Don’t plant your trees and shrubs too deep, you will smother them. Place the flare at soil level. During dry periods water slowly along the drip line and don’t overwater – plants can drown.
Don’t Smother your Trees this Spring – Learn How to Properly Mulch Your Trees!
Mulch: Mulch must not exceed 3 inches in depth and must be a minimum of 4 feet diameter around the bases. Too much mulch can be deadly to trees!
Edging: Edging must not exceed 1 inch depth around mulch beds.
Soil: After planting, do not add any extra soil on top of root balls or tree roots.
Additional mulching information is available in the City of Fredericksburg/Tree Fredericksburg brochure, Proper Mulching = Healthy Safe Trees.
For much more mulch information, read the Fredericksburg Department of Public Works’ Mulch Standards Fact Sheet