Many groundcover materials are sold in cubic yards. It’s an easy calculation. First, calculate the square footage of the area (length X width). Then determine how deep or thick the coverage should be as a portion of a foot. For example, 3 inches thick would be .25 of a foot, 6 inches would be .5. Multiply the square footage by this thickness. Then divide by 27. Your answer represents the cubic yards you need.
Hilton Landscape Supply