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Gardenly3D

Soil & Raised Bed Calculator

Enter your raised bed or garden plot dimensions to estimate how much soil you need — including volume, bag count, and total weight for any soil mix. Results are approximate and intended for planning purposes only; confirm final quantities with your supplier or a professional before ordering.

Calculate Your Soil

ft
ft
in

Volume Preview

Total Volume

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Bags Needed

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standard 1 cu ft bags

Estimated Weight

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With 10% Settling Buffer

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Recommended to account for soil settling

How to Calculate Soil for Raised Beds

  1. 1

    Measure your bed dimensions

    Measure the inside length, width, and depth of your raised bed in feet and inches. For L-shaped beds, measure each rectangular section separately.

  2. 2

    Choose your bed shape

    Select rectangle for standard beds or L-shape for corner beds. L-shaped beds are calculated as two joined rectangles for volume estimation.

  3. 3

    Select your soil mix

    Different soil types have different weights. Choose the mix you plan to use — garden soil mix is ideal for most raised beds, while potting mix works best for containers.

  4. 4

    Review and order

    Check the total volume in cubic yards for bulk delivery, or use the bag count for store purchases. Add 10% extra to account for settling.

Pro Tips

  • Fill raised beds with a mix of 60% topsoil, 30% compost, and 10% potting mix for the best growing results.
  • Add 10% extra soil to your order — fresh soil settles significantly in the first few weeks after filling.
  • For beds deeper than 18 inches, fill the bottom third with coarse material like wood chips or straw to save on soil costs.
  • Avoid using pure garden soil in containers — it compacts too much. Use potting mix instead for pots and planters.
  • Top off raised beds with 1-2 inches of fresh compost each spring to replace nutrients and volume lost to decomposition.
  • Line the bottom of raised beds with landscape fabric or hardware cloth to prevent weeds and burrowing pests.

Frequently Asked Questions

How much soil do I need for a 4x8 raised bed?
A standard 4×8 foot raised bed that is 12 inches deep needs about 32 cubic feet (1.19 cubic yards) of soil — roughly 32 standard 1-cubic-foot bags.
How deep should a raised bed be?
Most vegetables need at least 6-12 inches of soil depth. For root vegetables like carrots and potatoes, aim for 12-18 inches. Shallow-rooted herbs and lettuce can grow in beds as shallow as 6 inches.
What is the best soil mix for raised beds?
The classic raised bed mix is 60% topsoil, 30% compost, and 10% perlite or coarse sand. For a simpler option, a 50/50 blend of topsoil and compost works well for most gardens.
How much does a cubic yard of soil weigh?
Topsoil weighs about 1,100 lbs per cubic yard. Garden soil mix is around 1,000 lbs, potting mix about 600 lbs, and sandy loam around 1,200 lbs per cubic yard.
Should I buy soil in bags or bulk?
For beds under 1 cubic yard, bags are convenient and easy to transport. For larger projects, bulk delivery is generally far cheaper per volume than buying individual bags from the store.
How much does soil settle after filling?
Fresh soil typically settles 10-20% in the first month. Add extra soil when filling, and plan to top off beds after a few weeks of watering and settling.

Results are approximate and intended for planning purposes only. Material densities, coverage rates, and quantities are estimates that may vary based on actual conditions, product specifications, and installation methods. Always consult a professional for final specifications.

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