Estimate how much mulch is required for a given area at a specified depth. MULCH CALCULATING 101 If your wondering how much mulch will I need? use this formula - 1 cubic yard will cover an area 10x10 ft/3 inches deep - Or use our handy mulch calculator to figure out your mulch needs. BLACK DYED HARDWOOD MULCH - This mulch is also a double ground hardwood, dyed with a non-toxic colorant to help prevent fading. TRIPLE GROUND HARDWOOD MULCH - This our most popular mulch. It is dark brown (not dyed) and can be used in all types of landscaping applications. DOUBLE GROUND HARDWOOD MULCH - It is dark brown (not dyed) and can be used in all types of landscaping applications.