How much mulch do I need?
Enter the length, width and depth of the bed, pick your bag size, and you'll get the volume in cubic yards (or cubic metres) plus the number of bags to buy — instantly.
That's about 14 bags at 50 L each — or order the m³ in bulk and round up.
Volume = length × width × depth; bags = volume ÷ bag size, rounded up. Mulch settles, so 50–75 mm is a guideline depth, not a code value — adjust for your beds.
Common questions
- How much mulch do I need?
- Multiply the bed's length × width × depth to get the volume. A 10 ft × 10 ft bed at 3 inches deep is about 0.93 cubic yards (25 cubic feet) — roughly 13 bags of standard 2-cubic-foot mulch. Two to three inches is the usual spread depth.
- How many bags of mulch are in a cubic yard?
- A cubic yard is 27 cubic feet, so it takes about 14 standard 2-cubic-foot bags (27 ÷ 2 = 13.5, rounded up) or 9 of the larger 3-cubic-foot bags. Bulk by the yard is usually cheaper than bags once you pass roughly half a yard.
- How much does a yard of mulch cover?
- One cubic yard covers about 108 square feet at 3 inches deep, about 162 square feet at 2 inches, and about 81 square feet at 4 inches. Halve the depth and you roughly double the coverage — the calculator does the exact math for your bed.
- How deep should mulch be?
- As general garden guidance, 2–3 inches (50–75 mm) is the usual range: deep enough to suppress weeds and hold moisture, not so deep that it smothers roots. Keep mulch a few inches clear of trunks and stems — piling it against the bark ("volcano mulching") traps moisture and invites rot.
- Should I buy mulch in bags or in bulk?
- Bags are tidy for small beds and easy to carry; bulk by the cubic yard is cheaper and faster to spread on larger areas, but needs somewhere to tip it and a way to barrow it. The volume is identical either way — the calculator shows both the cubic yards and the bag count so you can compare.
Want the full walk-through? Read the mulch guide →
Reference & education only. Not professional, engineering, or code-compliance advice. Estimates are based on published model codes; local amendments and your Authority Having Jurisdiction (AHJ) govern. Always verify against the current adopted code and a licensed professional before doing work.
Last reviewed 2026-06.