Free Calculator
Raised Garden Bed Calculator — How Much Soil Do I Need?
Cubic yards of garden soil mix for raised beds and planters.
3. Enter Dimensions
Your order summary lands here
As soon as the dimensions are valid, you will see the recommended quantity, truckload count, and the ZIP pricing step.
Raised beds want a blend of topsoil, compost, and garden soil mix — not bare topsoil and not pure compost. Use this calculator to size the fill volume. Most home beds get a 60/30/10 blend of garden mix, topsoil, and compost.
How to use this raised garden bed calculator
- 1
Measure the bed
Inside dimensions only — length × width × depth of the bed walls.
- 2
Pick the depth
Use the bed wall height. Most raised beds are 8–18 inches deep. Vegetables want 12 inches minimum.
- 3
Pick the soil
Garden soil mix (default) is the best single-product fill. Real pro mixes blend garden mix + topsoil + compost.
- 4
Enter your ZIP
Florida ZIPs return delivered pricing per cubic yard.
How the math works
Volume in cubic yards equals Length × Width × Depth ÷ 27. A 4 ft × 8 ft bed at 12 inches deep is (4 × 8 × 1) ÷ 27 = 1.2 cubic yards.
Most raised beds settle 15–20% in the first season. The calculator buffer accounts for this — order to the brim of the bed, not the soil line you want after watering.
The classic ratio for a vegetable bed is 60% garden soil mix, 30% topsoil, 10% compost. For ornamentals, 80% garden mix and 20% topsoil is fine.
How much does raised garden bed cover?
Quick reference for how much area one ton and one cubic yard cover at common depths.
| Depth | 1 ton covers | 1 cubic yard covers |
|---|---|---|
| 1" | — sold by yard — | 324 sq ft |
| 2" | — sold by yard — | 162 sq ft |
| 3" | — sold by yard — | 108 sq ft |
| 4" | — sold by yard — | 81 sq ft |
| 6" | — sold by yard — | 54 sq ft |
| 12" | — sold by yard — | 27 sq ft |
Coverage is volume-based — one cubic yard always covers the same area at a given depth regardless of soil density.
Typical quantities by project
| Project | Depth | Area | Estimate |
|---|---|---|---|
| Standard 4 ft × 8 ft bed × 12" | 12" | 32 sq ft | ~1.2 cubic yards |
| Two 4×4 beds × 12" | 12" | 32 sq ft | ~1.2 cubic yards |
| Wide 4 ft × 12 ft × 18" | 18" | 48 sq ft | ~2.7 cubic yards |
| Tall planter 3 ft × 6 ft × 24" | 24" | 18 sq ft | ~1.3 cubic yards |
| L-shape ~50 sq ft × 12" | 12" | 50 sq ft | ~1.9 cubic yards |
Common ordering mistakes
From real deliveries, these are the mistakes we see most often. Avoiding any one of them saves a callback order.
Pure topsoil
Florida topsoil is sandy. Pure topsoil drains too fast for most vegetables. Blend with compost and garden mix.
Pure compost
Compost holds too much water and burns sensitive roots. Cap at 10–20% of the fill volume.
Bed too shallow
A 6-inch bed limits you to lettuce and herbs. 12 inches opens up most vegetables. 18 inches for root crops and tomatoes.
Forgetting drainage
A wood-bottomed bed with no drainage holes is a soup bowl. Either open-bottom over loosened native soil, or drill holes.
No settlement buffer
Beds settle 15–20% after the first heavy rain. Fill to the top and plan to top off mid-season.
Frequently asked questions
Ready to see delivered pricing?
Jump back to the calculator to price the exact quantity for your ZIP, or request a manual quote if the project needs special handling.