Measure your beds, pick a depth, and get the number for a bulk delivery or the exact bag count for the truck bed.
Bed measurements
sq ft
Bulk mulch to order
—
2 cu ft bags—
3 cu ft bags—
Total volume—
One cubic yard covers about 108 sq ft at 3 inches. Bulk beats bags on price once you pass roughly 2 yards — but bags win on clean handling and no driveway pile.
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Coverage tables for mulch, soil, gravel, sod, seed, paint, tile, flooring, fence, deck and pavers with waste built in — plus budget sheets, a shopping list, and a 1-ft layout grid. 9-page PDF.
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The mulch math
Mulch is a volume purchase: bed area times depth. The store sells it two ways — by the cubic yard in bulk, or in 2 and 3 cubic foot bags — and both come from the same simple formula:
Beds totaling 400 sq ft at the standard 3-inch depth need 100 cu ft — 3.7 cubic yards, or 50 two-cubic-foot bags. At typical prices that's the point where a bulk delivery costs meaningfully less than the bag aisle, even after the delivery fee.
Depth is the decision that matters
Two inches refreshes a bed that already has mulch. Three inches is the standard for a new bed — enough to hold moisture and block most weeds. Four inches is for serious weed suppression, but keep any depth pulled a few inches back from trunks and stems: mulch piled against bark ("volcano mulching") traps moisture and invites rot.
Frequently asked questions
How many square feet does a yard of mulch cover?
About 162 sq ft at 2 inches deep, 108 sq ft at 3 inches, and 81 sq ft at 4 inches. One cubic yard is 27 cubic feet, so divide 324 by your depth in inches for coverage.
How many bags of mulch equal a cubic yard?
13.5 of the 2 cu ft bags or 9 of the 3 cu ft bags. Comparing the per-yard price both ways is the fastest way to see when bulk delivery starts saving real money.
How deep should mulch be?
3 inches is the sweet spot for new beds — moisture retention and weed control without smothering roots. Go 2 inches for annual refreshes and never pile mulch against trunks or stems.
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