First, determine the total square footage you would like to cover, by taking the approximate length x width of your beds and adding the totals of all areas together. The easiest method is to divide that total square footage by 100, which will give you the total number of yards required to install mulch at 3" deep. For more detailed calculations, and additional options, please try out the mulch calculator on this page.
1 yard = 27 cubic feet (3' x 3' x 3')
1 yard = 10' x 10' area (or 100 sq. ft.) at 3" depth
1 yard = approximately 12-14 bags of mulch
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