Until the safety of treated wood is proven conclusively, we recommend you use a naturally rot-resistant wood like red cedar, black locust or redwood. Under most circumstances, these woods will last 10 â€“ 20 years when used for raised beds.
Wood options for Raised Garden Boxes. Redwood or Black Locust â€“ Definitely the best option for raised garden boxes in terms of longevity because they are naturally rot-resistant and have been known to last up to 20 years. Cedar â€“ Another rot-resistant wood, cedar can last 10-15 years and looks gorgeous.
The wood to use for a raised bed is your decision. Here are some options: Cedar and redwood are naturally water-resistant but can be expensive and hard to find. Hemlock, fir and pine are suitable materials for raised beds but aren't very long-lasting.
The key is to use "regular" pine boards and not pressure treated/preserved boards. Pine is not the best choice, however, because it is a soft wood and will not last as. and cons of cedar, recycled, and composites for raised garden beds: Cedar vs.. . mix be used to raise bed vegetable gardening instead of common soil?