Compost Needed for a Circular Garden

The Compost Needed for a Circular Garden calculator uses the area of the garden (π ⋅ r²) and the preferred depth of the compost to calculate how much compost is needed. 

INSTRUCTIONS: Choose units and enter the following:

• (`r`) Radius of the circular garden (radius = diameter ÷ 2)
• (`D`) Depth of the compost (two inches is standard)

Compost Needed for a Circular Garden: The calculator returns the answer in cubic feet. However this can be automatically converted to compatible units via the pull-down menu.

The Math / Science

Compost contains nutrients that are beneficial for plants. The use of compost reduces the need for chemical fertilizers, reduces compaction, encourages better drainage, and reduces stormwater runoff.

To find the compost needed for a circular garden, use the formula:

Compost = π ⋅ r² ⋅ D

where:

`r` = Radius of the circular garden (radius = diameter ÷ 2)

`D` = Depth of the compost (two inches is standard)