How to Calculate Mulch
What is Mulch?
A mulch calculator determines how many cubic yards of mulch or bark chips are needed to cover a garden bed to a specified depth. Mulch conserves moisture, suppresses weeds, moderates soil temperature, and improves soil as it decomposes.
Step-by-Step Guide
- 1Volume = Length (ft) × Width (ft) × Depth (in) / 324 = cubic yards
- 2Rule: 1 cubic yard covers 324 sq ft at 1 inch depth
- 3Recommended depth: 2–4 inches (too thin = weeds, too thick = root rot)
- 4Around trees: keep mulch 3–6 inches away from trunk ("mulch volcano" harms trees)
Worked Examples
Input
Bed 8 ft × 12 ft · 3 in depth
Result
≈ 0.74 cubic yards mulch needed
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