How much do I need? Square or Rectangle The area of a square or rectangular garden is easy to calculate. Simply multiply the length by the width by the depth or use our simple volume calculator. Circular Circular areas are also easy to calculate. Simply multiply 3.1415 by the radius, by the radius again, by the depth ~ or use our simple volume calculator.	Square or Rectangle   Garden width: in m (metres)   Garden length: in m (metres)   Mulch depth: in m (metres)   Required Volume: in m3 (cubic metres)          Circular   Garden radius: Radius is half the circles diameter in m (metres)   Mulch depth: in m (metres)   Required Volume: in m3 (cubic metres)