If you are using wood to make raised garden beds, you definitely want to use a wood that is designed to be outdoors. Popular woods for garden beds are: cedar, yew, redwood, juniper, black walnut, white oak, locust wood, spruce, pine and douglas fir. Read more about choosing the best wood for raised beds in this article.  There are a lot of other suitable materials for raised garden bed material other than wood too...like vinyl, recycled plastic or composite material - which are all great options as well.