Mulch is material spread over the soil surface to conserve moisture, moderate soil temperature, and suppress weed growth. For larger landscaping projects, mulch is typically purchased in bulk quantities. The term “yard of mulch” is a standard unit of volume used in the landscaping industry to measure loose materials, and it does not refer to a distance measurement.
Defining the Cubic Yard
A “yard of mulch” is the common term for one cubic yard, a precise measure of volume. This unit is defined as a cube that is three feet wide, three feet long, and three feet deep. Multiplying these dimensions reveals that one cubic yard contains exactly 27 cubic feet of material. This standardized measurement allows landscaping suppliers to accurately quantify loose materials like topsoil, gravel, and mulch.
Knowing the coverage area of a cubic yard is helpful for planning purchases. When applied at the common depth of two inches, one cubic yard of mulch covers approximately 162 square feet. If a deeper application of three inches is desired for better weed suppression or moisture retention, the same volume will cover about 108 square feet. Professionals generally recommend a depth between two and four inches, depending on the material and existing weed pressure.
How to Calculate Your Mulch Needs
Calculating the required amount of mulch begins with accurately measuring the area to be covered. Measure the length and width of the planting bed or area in feet, then multiply these two figures to find the total square footage. The next step is deciding on the desired depth of the mulch layer in inches.
The simplest approach involves a specialized conversion formula that accounts for the difference between square feet and cubic yards. The formula takes the total square footage (L x W) and multiplies it by the desired depth (D) in inches. This product is then divided by the constant 324, which is the number of square feet a cubic yard covers at one inch of depth.
Alternatively, a more direct method involves converting all measurements to feet before calculating volume. To use this method, convert the desired depth from inches to a fraction of a foot. Then, multiply the length, width, and converted depth to get the total volume in cubic feet.
Finally, divide the total cubic feet by 27, since there are 27 cubic feet in one cubic yard. For example, a 100 square foot area needing a three-inch layer requires about 25 cubic feet of material, which translates to just under one full cubic yard.
Bulk Versus Bagged Mulch
The term “yard of mulch” applies almost exclusively to bulk purchasing, where the material is delivered loose in a dump truck or loaded onto a trailer. This method is more cost-effective for larger projects because the consumer pays primarily for the material itself rather than the packaging and handling. Buying in bulk also offers a wider variety of mulch types and materials.
In contrast, bagged mulch is sold in smaller, pre-packaged quantities measured in cubic feet or quarts. A standard bag of mulch is often two cubic feet, though sizes vary. To purchase the equivalent of one cubic yard (27 cubic feet) using standard two-cubic-foot bags, one would need approximately 13.5 bags.
While bagged mulch is more expensive per unit of volume, it offers convenience for smaller areas or for projects with limited access for a large truck delivery. The bagged option also allows for easier transportation and handling, as the smaller volumes are much less unwieldy than moving a large pile of loose material.