Rain garden sizing calculator
PRORain garden area for the runoff you're capturing.
Inputs
Result
Rain garden area
100 sq ft
Recommended depth
4–8 in
The formula
Garden area = drainage area × soil factor.
Worked example
500 sq ft roof × 0.2 (sandy) = 100 sq ft garden.
Frequently asked
›How far from the house?
At least 10 ft from foundations.