🌱 Project Details
Soil Calculator: Exactly How Much Soil You Need
Use the calculator above to get cubic yards, cubic feet, cubic meters, bag counts, and a cost estimate. The guide below explains how to measure, how deep to fill for different projects, and when to choose bulk vs. bagged soil.
Quick links:
How to Use ·
Soil Depth by Project ·
Bulk vs Bagged ·
Allow for Settling ·
Measuring Tips ·
FAQs
How to Use the Soil Calculator
- Choose your area shape (Rectangle, Circle, or Custom).
- Enter dimensions (length, width, and soil depth).
- Select your garden purpose to see a recommended soil blend.
- Optional: add your ZIP code for climate-specific tips.
- Review your results: volume, bag counts, estimated cost, and a project summary.
How Deep Should Your Soil Be?
Depth drives root health, drainage, and yield. Use these ranges as a starting point and adjust for plant type and local conditions.
| Project Type | Recommended Depth | Notes |
|---|---|---|
| Vegetable garden beds | 12–18 in (30–45 cm) | Deeper (up to 24 in) for root crops and heavy feeders. |
| Flower beds | 8–12 in (20–30 cm) | Prioritize drainage; amend clay with compost. |
| New lawn (seed or sod) | 4–6 in (10–15 cm) | Top off with compost-rich mix for germination. |
| Topdressing an existing lawn | 1–2 in (2.5–5 cm) | Rake in thin lifts to avoid smothering grass. |
| Trees & shrubs | 18–36 in (45–90 cm) | Wider planting areas matter more than extreme depth. |
| Raised beds | 12–24 in (30–60 cm) | Match depth to bed height; ensure good drainage. |
| Containers & planters | Varies by pot size | Use high-porosity mix; avoid dense topsoil in pots. |
Recommended Soil Blends
- Vegetable Mix: ~40% topsoil · 40% compost · 20% sand for nutrient-hungry crops.
- Lawn Mix: balanced topsoil with compost to improve seed-to-soil contact.
- Flower Bed Mix: lighter, well-drained soil; incorporate perlite or coarse sand if needed.
Bulk Soil vs. Bagged Soil—Which Should You Buy?
Your results show both options. Use this quick comparison to decide:
Bagged Soil
- Convenient for small projects and tight access.
- Easy to store and keep dry.
- Higher cost per cubic foot.
Bulk Soil
- Best value for 1+ cubic yard projects.
- Delivered to your driveway—move with a wheelbarrow.
- Requires space and a plan for same-day spreading.
Handy conversions: 1 cubic yard = 27 cubic feet ≈ 40 bags (1 cu ft each) ≈ 20 bags (1.5 cu ft each).
Don’t Get Caught Short—Account for Soil Settling
After watering and a few weeks of use, soil typically settles by 10–20%. Your calculator includes a settlement slider so you can add a buffer. Example: base volume 40 cu ft → +15% settling = 46 cu ft final volume to order.
Measuring Tips for Accurate Results
- Measure the inside dimensions of raised beds.
- For circles, measure the diameter (edge to edge) and enter depth separately.
- For irregular shapes, split the area into rectangles/circles, calculate each, then add them together.
- On slopes, measure average depth; if in doubt, round up slightly.
Soil Calculator FAQs
How many bags are in a cubic yard of soil?
About 40 bags if each bag is 1 cubic foot, or about 20 bags if each bag is 1.5 cubic feet.
How much soil do I need for a 4×8 raised bed?
At 12 inches deep, a 4×8 bed holds 32 cubic feet—just over 1 cubic yard. Increase depth to 15 inches and you’ll need ~40 cubic feet before settling.
What’s the difference between topsoil and garden soil?
Topsoil is basic mineral soil. Garden soil is enriched with organic matter (like compost) for better drainage and nutrition. For vegetables and flowers, a garden mix performs best.
Should I buy bulk or bagged soil?
Under about one cubic yard, bags are convenient. For bigger projects, bulk is usually more economical—especially with delivery.
How heavy is a cubic yard of soil?
Roughly 1,500–2,200 pounds depending on moisture and composition. Plan wheelbarrow trips and help accordingly.