A cubic yard of mulch equals 27 cubic feet. The number of bags needed to make up one cubic yard depends on the bag size:

• For 2 cubic feet bags, you need about 13.5 bags per cubic yard.
• For 3 cubic feet bags, you need about 9 bags per cubic yard.
• For 1.5 cubic feet bags, you need about 18 bags per cubic yard.
• For 1 cubic foot bags, you need 27 bags per cubic yard

Coverage per bag also depends on the desired mulch depth. For example, a 2 cubic feet bag covers approximately:

• 24 sq. ft. at 1 inch deep,
• 12 sq. ft. at 2 inches deep,
• 8 sq. ft. at 3 inches deep,
• 6 sq. ft. at 4 inches deep

To calculate how many bags you need for your yard, measure the area in square feet, decide the mulch depth in inches, and use this formula:

Bags of mulch=Square footage×Depth (in inches)12×Bag size (in cubic feet)\text{Bags of mulch}=\frac{\text{Square footage}\times \text{Depth (in inches)}}{12\times \text{Bag size (in cubic feet)}}Bags of mulch=12×Bag size (in cubic feet)Square footage×Depth (in inches)​

For example, for a 100 sq. ft. area with 3 inches depth using 2 cu. ft. bags:

100×312×2=12.5 bags\frac{100\times 3}{12\times 2}=12.5\text{ bags}12×2100×3​=12.5 bags

This method helps you estimate the number of bags needed to cover your yard at the desired depth