How much mulch do I need for a 4×20 bed?
≈ 10 bags (2 cu ft)
That’s about 0.74 cubic yards to cover a 4×20 bed at a 3″ depth.
A 4 ft × 20 ft bed is 80 square feet. At a 3-inch mulch depth (the sweet spot for weed control + moisture), that’s 20.0 cubic feet — about 10 standard 2-cubic-foot bags, or 0.74 cubic yards in bulk.
| Bed area | 80 sq ft |
| Depth | 3 in |
| Volume | 0.74 cu yd (20.0 cu ft) |
| 2-cu-ft bags | 10 bags |
Bulk (by the yard) is usually cheaper above ~10 bags. Refresh 1–2″ yearly rather than re-mulching full depth.
Change the size → open the mulch calculatorGrab the supplies
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