Independent buying guides for balcony and small-space gardeners

Potting Soil Calculator

Enter your container shape and size to see how much potting mix to buy and how heavy it will be once watered.

Result

Potting mix needed
18.5 L
Dry quarts
16.8
Cubic feet
0.65
Wet weight (approx.)
13-17 kg

Wet potting mix weighs roughly 0.7-0.9 kg per litre. Check your balcony's load limits before adding large containers.

How this calculator works

Round volume = pi x radius squared x depth. Rectangular volume = length x width x depth. Cubic inches are converted to litres (1 L = 61.02 cu in), dry quarts and cubic feet, which is how bagged soil is sold.