How the mulch calculator works
Bed area x depth gives volume. A 10 ft x 10 ft bed at 3 inches deep needs 25 cu ft — about 0.93 cubic yards or 13 x 2 cu ft bags. The calculator adds your waste allowance (5% by default) for settling and uneven beds.
Depth guidance: 3 inches is the standard for weed control and moisture retention; 2 inches for a light top-up. Mulch settles 10–20% in the first weeks, so a fresh 3-inch layer will look thinner by summer. For larger beds, bulk delivery is far cheaper per yard than bags.
Edging the bed with stone? Try the gravel calculator for a stone border.