Bark Chip Coverage Calculator

About this calculator

Bark chip mulch coverage is a simple volume calculation: the cubic volume needed to cover a bed is bed area × desired depth, and dividing that by the cubic volume in a single bag tells you how many bags to buy. Standard bags are typically sold as 2 cubic feet (about 56 litres), and most guides recommend a mulch depth of 2 to 4 inches (5–10 cm) for weed suppression and moisture retention without smothering plant roots.

Gardeners and landscapers run this calculation before a trip to the garden center because underestimating leaves a visibly thin, patchy bed and a second trip, while overestimating wastes money on bags that go unused — and depth matters more than most people expect, since doubling the depth doubles the volume and therefore the number of bags needed.

This calculator takes your bed area, the depth you want and your bag size and returns exactly how many bags to buy, rounded up so you don't come up short partway through spreading.