How to use it
- Pick metric or US units.
- Enter the length, width and soil depth of one bed, and how many identical beds you are filling.
- Set the allowance for settling and the size of the bags you plan to buy.
How it works
Volume = length × width × depth × beds × (1 + extra ÷ 100). In US mode 1 ft³ = 0.0283168 m³ and 1 yd³ = 27 ft³. Bags = volume ÷ bag size, rounded up.
Worked example
One 8 × 4 ft bed filled 12 inches deep: 8 × 4 × 1 = 32 ft³. With 10% extra that is 35.2 ft³, or 1.30 yd³. In 1.5 ft³ bags: 35.2 ÷ 1.5 = 23.5, so buy 24 bags.
Tips
- Measure the inside of the frame, not the outside.
- If you also fill the bottom with logs or branches, subtract that depth.
- Bulk delivery is usually cheaper than bags above about 1 yd³ (0.75 m³).