How Deep Should a Raised Bed Garden Be?

Walls of all heights can be garden features, but certain guidelines apply to raised beds.

6-Inch Minimum

In general, a bare minimum of 6 inches is recommended by the Cornell Extension Services. More may be necessary if the existing soil at the site is poorly drained or sandy. If a vegetable garden is intended, the Texas AgLife Extension Service recommends 12 to 18 inches of depth.

3-Feet Maximum

Regardless of other factors, the Cornell Extension Services suggests limiting retained bed height to under 3 feet. This allows gardeners to tend the beds more comfortably.

Bottom Line

Optimal depth of a raised bed depends on the planned plantings and the intended site, but Cooperative Extension Services agree on a range of 1 to 3 feet for the best results.

References

• Texas AgriLife Extension: Building a Raised Bed Garden
• Cornell Cooperative Extension: Raised Bed Gardening