Introduction
Building a raised bed garden is exciting, but figuring out how much soil you need can be tricky. Our Raised Bed Soil Calculator works out how much soil your bed needs. Just enter the length, width, and depth of your raised bed, and the tool will tell you exactly how much soil to buy. This saves you time, money, and extra trips to the garden center. This calculator helps you get the right amount of soil every time, for a single bed or a whole garden. No more buying too much or too little, just the perfect fill for healthy plants and strong roots.
How to Use Our Raised Bed Soil Calculator
Enter the size of your raised bed below, and this calculator will tell you exactly how much soil you need to fill it.
Length: Enter the length of your raised bed in feet or inches. Measure from one end to the other along the longest side.
Width: Enter the width of your raised bed in feet or inches. This is the shorter side of your bed.
Depth: Enter how deep your raised bed is in feet or inches. This is the height of the walls from the bottom to the top. Most raised beds are between 6 and 12 inches deep.
Results: The calculator will show you the total amount of soil you need in cubic feet and cubic yards. Cubic yards is the unit most garden centers and soil suppliers use when selling soil in bulk, so this number helps you know exactly how much to order.
Raised Bed Soil Calculator
A raised bed is a garden built on top of the ground, usually held in place by a frame made of wood, stone, or metal. Raised beds are popular because they give you better control over your soil, drain water more easily, and keep weeds out. They also warm up faster in spring, which means you can start planting sooner.
How Much Soil Do You Need?
Figuring out the right amount of soil for your raised bed is one of the most important steps before planting. If you add too little soil, your plants won't have enough room for their roots to grow. Too much soil can be a waste of money. This calculator helps you find the exact volume of soil you need based on the size of your raised bed.
Understanding Soil Volume
Soil volume is measured in cubic feet or cubic yards. To find the volume, you multiply the length, width, and depth of your raised bed together. Most raised beds are between 6 and 12 inches deep. A depth of at least 6 inches works for herbs and lettuce, but deeper beds of 12 inches or more are better for tomatoes, carrots, and other plants with long roots.
What Kind of Soil Should You Use?
The best soil mix for raised beds is a blend of three things:
- Topsoil – makes up the bulk of your bed and gives structure
- Compost – adds nutrients that feed your plants
- Perlite or coarse sand – helps with drainage so roots don't sit in water
A common and trusted recipe is 60% topsoil, 30% compost, and 10% perlite or sand. This mix gives your plants a rich, well-draining home to grow in. You may also want to add a layer of pea gravel at the bottom of deeper beds to improve drainage further.
Helpful Tips
Keep in mind that soil settles over time. After filling your raised bed, the soil level can drop by 10 to 20 percent within the first few weeks. It's a good idea to buy a little extra soil so you can top it off later. Also, adding a fresh layer of compost each season keeps the soil healthy and full of nutrients for your next round of plants.