Free tool
Raised Garden Bed Soil Calculator
Measure the inside of the bed, not the outside of the frame, and enter the depth you want the soil to finish at. Add a row for each bed and this totals them.
What are you working on?
Choose the shape that best matches your area.
Enter your measurements
Use feet or metres. We’ll do the math.
How deep do you want it?
Common depths shown for each material.
Choose your material
Select a material to see product-specific recommendations.
Fresh bulk soil settles by roughly a tenth once it is watered in. We add 10 percent so you are not topping the beds up two weeks later.
Also need fabric?
Landscape fabric goes under the rock, and it is measured differently
Fabric is sold by the linear foot off a roll, so the amount depends on the roll width and the overlap at the seams. The fabric calculator lays out the strips and gives you the length to order.
Quantity Help
Area and depth in, cubic yards out — settling allowance included.
Complete Pricing
Product, service, delivery and tax, before you order.
Delivered or Loaded
We bring it to you, or load your open pickup at the yard.
We Make It Right
If something goes wrong with the part we handle, we fix it.
Getting the depth right
- A tall frame does not have to be soil all the way down. Filling the bottom third with coarse material and the top 12 inches with garden soil grows the same vegetables for less.
- Ten to twelve inches of good soil handles almost every home vegetable except long carrots and parsnips.
- Soil settles. Fill a little proud of the frame rather than level with it.
The maths behind it
Length times width gives square feet. Multiply that by the depth in inches, then divide by 324. The answer is cubic yards. One cubic yard covers 324 square feet at 1 inch deep, or 100 square feet at about 3¼ inches deep.
The 324 comes from a cubic yard being 27 cubic feet, and 27 times 12 inches is 324. Nothing else is going on, which is why you can check this calculator against a tape measure and a phone.
Materials this suits
Garden Soil Mix
Ready-to-plant soil for gardens, beds, and planters
Filling raised vegetable and flower beds · Building new in-ground garden beds
Mushroom Manure
Aged compost for richer, more workable garden soil
Mixing into existing vegetable-garden soil · Improving flower beds
Sandy Fill
Economical sand and rock mix for deeper landscape fill
Building up deep low areas · Raising grades beneath topsoil or Lawn Soil Mix
Common questions
How much soil do I need for a 4 by 8 raised bed?
A 4 by 8 foot bed filled 12 inches deep needs about 1.2 cubic yards of soil, or about 1.3 cubic yards once you allow for settling. At 10 inches deep it is closer to 1 cubic yard.
How deep should a raised garden bed be?
Ten to twelve inches of soil suits nearly every home vegetable. Salad greens and herbs are happy at 8 inches. Carrots, parsnips, and potatoes do better at 12 or more.
Can I fill a raised bed with just compost?
We would not. Straight compost, including mushroom manure, is too rich and holds too much water to grow in on its own. Use a garden soil blend as the body of the bed and mix compost through the top third.
Is bulk soil cheaper than bagged soil for raised beds?
Per cubic yard, yes, and the gap widens once you are past a bed or two. One cubic yard is 27 cubic feet of soil, which is a lot of bags to carry and open. The trade-off is that bulk arrives as a pile, so you need somewhere to put it and a wheelbarrow to move it.