Guide
How much mulch do I need?
Square footage, depth, and the size of the bag. Here is the calculation, with an example.
The calculation
- Measure the bed in square feet. A curved bed is easier to draw on a satellite view than to tape.
- Choose the depth: 2 to 3 inches of mulch is common; 3 in is a good default.
- Cubic feet = square feet × depth in inches ÷ 12.
- Cubic yards = cubic feet ÷ 27. Bags = cubic feet ÷ bag size, rounded up.
Example
A bed of 12 × 20 ft is 240 sq ft. At 3 in deep: 240 × 3 ÷ 12 = 60 cu ft, or 2.22 cu yd. In 2 cu ft bags, that is 30 bags; in bulk, a little over 2 cubic yards.
Bags or bulk?
Bags are 2 or 3 cu ft. Beyond two or three cubic yards, bulk from a landscape yard usually costs less per yard, plus delivery. Compare both: the volume is the same.
Several beds
Add the beds before you count the bags: a bag opened for one bed is finished on the next. Topsoil and compost follow the same calculation, often at 4 in and 2 in.
With Landscaping Calc
Draw each bed on the satellite view or type its dimensions; the app adds the beds of the project into one mulch line, in cubic yards, bags, big bags or truckloads. See Mulch calculator.
