Calculate cubic feet, cubic yards, and 40-lb bags of garden soil, compost, and vermiculite for rectangular and circular raised garden beds.
Cross-section demonstrates structural reinforcement elevation on concrete chairs per ACI 302.
Total Soil Blend Volume Required
Optimal 60/40 Garden Mix Split
1.4 yd³ Screened Topsoil | 0.9 yd³ Organic Compost
| Item / Material Spec | Quantity | Unit / Package | Installation Notes |
|---|---|---|---|
| Screened Native Loam Topsoil (60% blend) | 1.4 | Cubic Yards | Provides mineral structure and moisture retention |
| Aged Mushroom or Organic Compost (40% blend) | 0.9 | Cubic Yards | Rich organic microbial matter and root aeration |
| Heavy-Duty Hardware Cloth Wire (1/2-in mesh) | 64 | Square Feet | Stapled to bed bottoms to block burrowing gophers/moles |
Cost of raw lumber, concrete, shingles, wire, or stone without equipment rentals or labor.
Full installation: permits, site prep, skilled trade labor, equipment, and structural warranty.
Average trade labor savings if executed as a skilled DIY homeowner project.
Skip the heavy equipment rentals, structural liabilities, and municipal permit delays. Connect directly with pre-screened, licensed, and insured trade specialists in National Average.
Standard commercial specifications and pre-calculated project benchmarks.
| Bed Dimensions (L×W×D) | Cubic Feet | Cubic Yards | 1.5 Cu Ft Retail Bags | Bulk Delivery Cost |
|---|---|---|---|---|
| 4' × 4' × 12" (Single) | 16.0 cu ft | 0.59 yd³ | 11 Bags | $65 – $95 (Bags) |
| 8' × 4' × 12" (Standard) | 32.0 cu ft | 1.19 yd³ | 22 Bags | $95 – $140 |
| Two 8' × 4' × 12" Beds | 64.0 cu ft | 2.37 yd³ | 43 Bags | $175 – $240 |
| Four 8' × 4' × 18" Deep | 192.0 cu ft | 7.11 yd³ | 128 Bags (Order Bulk) | $380 – $520 (Bulk Truck) |
Raised bed soil should maintain an organic matter level of 8% to 15% and a pH between 6.2 and 6.8 for optimal nutrient uptake. Never fill raised beds with unamended native yard clay, which compacts and drowns plant root systems.
A 4' × 8' × 1' raised bed holds 32 cubic feet of soil. If buying standard 1.5 cubic foot bags, you need 22 bags. If buying 2.0 cubic foot bags, you need 16 bags.
If your garden requires more than 1.5 to 2.0 cubic yards (roughly 30+ bags), ordering bulk soil delivered by a local landscape supplier is typically 40% to 50% cheaper and saves hours of lifting.
The gold standard is 60% screened topsoil, 30% quality organic compost (mushroom or manure compost), and 10% aeration amendment (perlite, vermiculite, or coarse sand).
Freshly placed loose soil settles between 15% and 20% after the first few deep waterings. Fill your beds completely to the top rim so settling leaves 2 inches of lip.