Mulch calculator
Enter the area and how deep you want the mulch. You'll get the volume in cubic feet, cubic yards, and bags.
Wood mulch works best at 5–8 cm (2–3 in); keep it off plant stems.
How this is calculated
Volume = area × depth ÷ 12 (to convert inches to feet). Cubic yards = cubic feet ÷ 27. Wood mulch is usually applied 2–3 in deep; deeper than that can keep water and air from the soil. Keep mulch a couple of inches clear of plant stems and tree trunks.
Common questions
What depth of mulch should I use?
2-3 in of wood or bark mulch around vegetables and ornamentals is the standard range. Less than that breaks down too fast to suppress weeds well; more can starve roots of oxygen and hold too much moisture against stems.
Does mulch need to be replaced every year?
Organic mulch (wood chips, straw, shredded leaves) breaks down and feeds the soil, so topping it up once a year to maintain depth is normal - you're rarely starting from zero again.
Should I mulch right up to plant stems?
No - keep mulch 2-3 in clear of stems and tree trunks. Mulch piled against a stem holds moisture there and encourages rot and pests.