Page 15 of the Mulch And Landscaping archive. Return to page one for the full tag description.
The durable approach is to remove existing weeds, keep organic debris from building up and maintain sufficient gravel depth. Spot treatment is more effective when combined with physical maintenance instead of relying on one.
A broad 2–4 inch layer is a common practical range for many landscapes, but keep mulch pulled back from direct contact with the trunk and avoid piling a volcano around the tree base.
Measure the bed’s square footage and multiply by the desired depth in feet to get cubic feet. Divide by 27 for cubic yards. A 3-inch layer uses 0.25 feet as the depth.