🌱Mulch Calculator: How Much Mulch Do I Need?
Tell us the size of your bed and how deep you want it — we will do the digging (in numbers).
Your garden bed
You'll need about
1.02 cubic yards
or 14 bags of 2 cu ft · 0.78 m³
2–3 inches is the sweet spot. Keep mulch a hand's width away from tree trunks so they can breathe.
Popular sizes & projects
How it works
- Area = length × width (sq ft)
- Volume = area × depth in inches ÷ 12 (cu ft)
- Add your waste factor
- Cubic yards = cu ft ÷ 27, and bags = cu ft ÷ 2
Worked example
A 20 × 5 ft bed is 100 sq ft. At 3 in deep: 100 × 3 ÷ 12 = 25 cu ft. With 10% waste: 27.5 cu ft = 1.02 cu yd, or 27.5 ÷ 2 = 14 bags.
Questions people ask
2–3 inches for most beds. Go up to 4 inches for weed-heavy spots, but keep it thinner near plant stems.
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Last updated September 28, 2026. These results are friendly estimates to help you plan — always double-check before buying or making big decisions.