Soil for a 4 × 12 ft raised bed, by depth
The "with settling" column adds 10%. Bag counts are for 1.5 ft³ and 2 ft³ bags.
| Soil depth | To fill | With settling | Cubic yards | 1.5 ft³ bags | 2 ft³ bags |
|---|---|---|---|---|---|
| 6 in | 24.0 ft³ | 26.4 ft³ | 0.98 | 18 | 14 |
| 8 in | 32.0 ft³ | 35.2 ft³ | 1.30 | 24 | 18 |
| 10 in | 40.0 ft³ | 44.0 ft³ | 1.63 | 30 | 22 |
| 12 in | 48.0 ft³ | 52.8 ft³ | 1.96 | 36 | 27 |
| 18 in | 72.0 ft³ | 79.2 ft³ | 2.93 | 53 | 40 |
What goes in it
Fill to about an inch below the rim. Common recipes are equal parts compost, peat moss (or coco coir) and vermiculite, or a cheaper blend of screened topsoil and compost with some aeration. For a 12 inch 4 × 12 bed, that is about 17.6 ft³ of each ingredient in a thirds mix. See the raised bed soil guide for the options.
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Tools & materials for this project
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Frequently asked questions
How much soil for a 4x12 raised bed?
Filled 12 inches deep it holds 48.0 ft³. With 10% for settling, buy about 52.8 ft³ (1.96 cubic yards).
How many bags of soil for a 4x12 raised bed?
At 12 inches deep, 36 bags of 1.5 ft³, or 27 bags of 2 ft³. Bulk delivery is cheaper once you need more than about 20 to 30 ft³.
What is the mix for a 4x12 raised bed?
For an equal-thirds mix at 12 inches deep, about 17.6 ft³ each of compost, peat moss or coco coir, and vermiculite. A cheaper alternative is topsoil and compost, with some perlite or coarse sand.
Related sizes and guides
Estimates only. Results assume standard materials and simple shapes. Supplier products vary, and the final call on quantity, structure and safety is yours. Check your local code and your supplier's guidance before ordering.