How Much Dirt in My Flower Bed?

Plan ahead so you don't make costly mistakes.

Your raised beds look gorgeous, but now it's time to fill them. If you're moving soil from one area in the garden to another, you can simply eyeball it. But, if you're ordering it from a landscaping firm, you'll need to plan ahead.

Calculations

To determine how much soil you need, first calculate the square feet of your space. To calculate square or rectangle flower beds, simply multiply the width by the length. Then determine the volume. Decide how many inches high you want your flower bed and divide this number by 12. Then multiply the result by the area. This number is the total cubic feet of soil you'll need to fill your bed. To convert cubic feet to cubic yards--which is how soil is usually sold--divide the number by 27.

Considerations

If you're bringing in soil from another source, your two options are usually to buy it in bags from a nursery or home store, or buy it in bulk from a landscaping firm. Buying it in bulk is usually the better deal unless you have a small flower bed. When you buy it in bulk, you may also have the option to custom blend your soil with compost and other amendments.

Recommendations

When calculating how much soil you need, order a bit more than your estimate. You can always use extra soil in another spot in the garden, but if you don't order enough, your entire project will be delayed, and you may pay additional delivery charges.

References

• Washington State University Extension: Garden Math

Resources

• Oregon State University Extension: Buyer Beware: You Could Be Getting Just About Anything
• University of New Hampshire Cooperative Extension: Buying Topsoil