Calculator Uni

Mulch Calculator

Cubic yards and bags of mulch for your garden beds.

Bed dimensions
sq ft
in

Mulch needed

1.85 cu yd

2 cu ft bags

25

3 cu ft bags

17

Rule of thumb

1 cu yd covers ~100 sq ft at 3"

Depth does the work

Two to three inches suppresses weeds and holds moisture; one inch is decoration; four-plus suffocates roots and invites rot against trunks. Area × depth ÷ 27 (in feet) gives cubic yards — bulk delivery beats bags above about one yard.

Keep it off the stems

Leave a 2–3 inch gap around trunks and stems — 'mulch volcanoes' rot bark and harbor rodents. Organic mulches settle about an inch a year, so an annual top-up of one inch maintains the bed without endless accumulation.

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