Mulch Calculator

Most landscaping guides recommend 2-3 inches of mulch for established garden beds — enough to suppress weeds and retain soil moisture, without piling mulch so deep (4+ inches) that it restricts water and oxygen from reaching plant roots or promotes fungal growth against stems.

Depth is measured in inches but area is in square feet, so the calculator divides the depth by 12 to convert it to feet before multiplying by area — this gives cubic feet, which is then divided by 27 (cubic feet per cubic yard) to get the more commonly quoted bulk-mulch unit.

For small areas (a few cubic yards or less), bagged mulch (typically 2 cubic feet per bag) is usually more convenient despite costing more per cubic yard. For large areas, buying bulk mulch by the cubic yard from a landscaping supplier is significantly cheaper — the calculator shows both units so you can compare either purchasing option.

No — it calculates the volume needed for your specified starting depth only. Organic mulch compresses and decomposes over time, so many gardeners add a thinner top-up layer (an extra inch or so) annually rather than recalculating from zero each year.