The wood used in organic raised garden beds is important, especially when it comes to your food supply. It needs to do two things:
To build a garden bed, you need wood, fasteners, and connection pieces.
Many people do not realize that there are natural materials that meet the requirements of organic raised garden beds, and exceed the performance of pressure treated lumber. They are more expensive, but will give you the peace of mind of a natural product. We offer two wood species that meet these requirements: Locust and White Oak. Both are premier species that resist ground contact due to their inherent resistance. They can be made in any dimensions, as we are a custom lumber production facility. We typically produce materials 1"-3" thick, 6"-12" wide, and 8' to 20' long. The longer and the wider, the more expensive, so if you have a budget, look toward shorter and thinner.
If you are looking for connection materials, those that join corners, we have friends that make these components. We haven't gotten to the point that we make kits for both wood and connection, but we can put you in touch with people who provide materials, as well as people who do it.
If price is a concern for an organic garden bed, and you want to sacrifice performance (i.e., how long it will last), we can provide the material in other wood species at a reduced cost. Just realize the ground contact performance is quite limited, and will need to be rebuilt fairly often.