Mulch Calculator

Find how much mulch you need to cover a garden bed.

Bed length

Bed width

Depth

Bag size

Mulch volume 1.852

Mulch volume 50

Bags needed (bags) 25

Formula: ft³ = length × width × depth/12 ; yd³ = ft³ ÷ 27

Step-by-step with your numbers:

1. Values used:

2. Bed length = 20

3. Bed width = 10

4. Depth = 3

5. Bag size = 2

7. Mulch volume = 1.852

8. Mulch volume = 50

9. Bags needed = 25bags

Did we solve your problem today?

Estimate the mulch needed to cover a garden bed at your chosen depth, in cubic yards (bulk) and bags.

The math behind it

Volume (ft³) = length × width × depth (depth converted to feet). Cubic yards = ft³ ÷ 27. Bags = ft³ ÷ bag size.

20 × 10 ft bed at 3 in → 50 ft³ = 1.85 yd³ (25 × 2 ft³ bags).

How deep should mulch be?

2–3 in for most beds; deeper smothers plants and can hold too much moisture.