Ask Mr. Smarty Plants

Construction work is a little out of our line, but since we know a lot of gardeners, particularly in Central Texas where there's not much dirt in the ground, are moving towards raised beds for drainage, enrichment, etc. We are going to recommend some websites that will answer your questions a whole lot better than we can.

First, this eartheasy site Raised Garden Beds has detailed construction specifications, materials recommendations, etc. In particular, note the paragraph about treated wood. Treated lumber has several types of preservatives, among them different types of arsenates. There is growing concern about the dangers of arsenic leaching into the ground or rubbing off on people's hands from the treated wood. Rather than treated lumber, if you wish to use wood, try red cedar, black locust or redwood. Recycled composite plastic lumber is another alternative.

Another website, Texas A&M Horticulture Extension on Building a Raised Bed Garden, addresses some other materials you might want to try, like brick or stone. And, most of the home improvement and garden stores carry modular molded cement blocks that can be stacked mortarless in varying shapes and sizes. You will have to make the decision on which product works best for you, based on cost, labor, and how much area you want to have in raised beds.