How Much Mulch Do I Need Over Soil? How Much Mulch Do I Need Over Soil?
To protect fertile soil, a layer of mulch may be the best solution. How much mulch you will need depends on what it is being used for, and how it is being placed. For a path or trail, mulch should be about 2 inches thick, but in a flower bed, too much mulch will inhibit plant growth. If seeds are expected to sprout, mulch coverage should be minimal.
Thickly applied mulch prevents soil erosion, and reduces the wear of frequent traffic. Lesser amounts provide protection against moisture evaporation and weed invasion. The more mulch you apply, the more protection it offers, but thick mulch may inhibit plant growth, and will almost certainly prevent seeds from sprouting. For most purposes, 1 inch of mulch coverage is plenty.
Calculating Mulch Required
Garden mulch should be around 1 inch thick. To calculate how much is required, multiply the length of the area by the width. If you prefer to use more than one inch of mulch, multiply the length times the width, and the multiply that number by the depth you wish to use. Other than being used for paths or trails, mulch should never be applied more than 2 inches deep.