DIY Cost Tools
Mulch Calculator
Estimate cubic yards of bulk mulch or standard two-cubic-foot bags for a rectangular garden or landscape bed.
How this calculator works
Volume = length × width × depth. Cubic yards = cubic feet ÷ 27. Bag count is based on a standard 2-cubic-foot bag.
How the estimate works: The calculator uses your measurements, unit conversions, waste allowance, and product coverage to create a planning quantity. Review the formula shown above, then read the matching guide below before ordering. See How Our Calculators Work for assumptions and limitations.
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Choosing a mulch depth
A layer around 2–3 inches is common for established beds. Too little may not suppress weeds; too much against trunks, stems, or building materials can retain unwanted moisture. Measure several points when a bed has an irregular shape and divide complex areas into smaller rectangles.
Bulk or bags?
Bulk mulch can be economical for large projects but may include a delivery fee and minimum quantity. Bags are easier to transport and place in small or hard-to-reach beds. Prices and bag sizes vary, so enter your local figures.
Mulch-bed example
A 20-by-10-foot rectangular bed covered 3 inches deep needs 50 cubic feet of mulch. Dividing by 27 gives about 1.85 cubic yards. The same volume equals 25 bags if each bag contains 2 cubic feet. Round purchases to available bag sizes or the supplier’s bulk increment, and add a modest allowance for uneven ground and settling when appropriate.
Measure planted and unplanted areas correctly
Divide curved beds into smaller shapes and subtract large areas occupied by patios, rocks, or dense groundcover. Measure the intended finished depth after accounting for existing mulch; repeatedly adding full-depth layers can bury plant crowns and hold excess moisture against trunks or structures. Product texture and moisture affect bulk appearance, while delivery, spreading, edging, weed removal, and fabric are separate costs.