Mulch calculator
Bed area at the depth you spread it, in the cubic yards a landscape yard sells.
Mulch
Bed area at the depth you spread it, in the cubic yards a landscape yard sells.
Two inches refreshes a bed, three suppresses weeds. Bags are 2 cu ft — 13.5 of them to the yard.
$70
1.85 cubic yards of bark mulch, bulk at $38.00 / cu yd
Free. No signup. The quantities carry over as line items.
How this mulch calculator works
Bed area at the depth you actually spread it. Landscape yards sell by the cubic yard; big-box stores sell 2 cu ft bags, and thirteen and a half of them make a yard.
The formula
cu yd = area × depth(in) ÷ 324 · bags = ⌈cu yd × 13.5⌉
Assumptions and defaults
| Refresh depth | 2 in |
| Weed-suppressing depth | 3 in |
| Bag size | 2 cu ft |
| Bags per yard | 13.5 |
Pro tips
Three inches suppresses weeds; two just refreshes colour. Below two you are paying for a look that lasts a month.
Keep mulch off the trunk flare. Volcano mulching around a tree looks tidy and slowly kills the tree.
Bulk beats bags over about three yards, even after delivery. Under a yard, bags are easier and you will not have a pile in the driveway.
Common questions
How much mulch do I need?
Bed area in square feet times depth in inches, divided by 324. A 200 sq ft bed at 3 inches is 1.85 cubic yards.
How many bags of mulch in a yard?
13.5 at the standard 2 cubic foot bag. Round up — nobody sells half a bag.
How deep should mulch be?
Two to three inches. Deeper holds water against stems and starves roots of air.
When should mulch be replaced?
Top it up once a year, usually spring. Pull back and turn what is there before adding, or you build an impermeable mat over the years.