How much mulch do you need?
Find the area of your bed by multiplying its length by width. Multiply that by the depth in feet, then divide by 27 to get cubic yards. A cubic yard is the quantity commonly used for bulk landscape deliveries.
For bagged mulch, this calculator uses 2 cubic feet as a standard bag size. Bag sizes vary, so use the quantity printed by your supplier when shopping.
Leave a small gap around plant stems and tree trunks. Mulch piled against them can hold excess moisture.
Should you buy mulch by the bag or yard?
Bags can make sense for a small bed or a quick top-up. Bulk mulch is often simpler for larger areas, but delivery charges, storage space, and minimum quantities matter too.