Vegetable garden bed construction materials should be chosen carefully. Some concerns exist regarding the use of pressure-treated timber. Pine that was treated using chromated copper arsenate or CCA, a toxic chemical mix for preserving timber that may leach chemicals into the soil which in turn can be drawn up into the plants, is a concern for vegetable growers, where part or all of the plant is eaten. If using timber to raise the garden bed, ensure that it is an untreated hardwood to prevent the risk of chemicals leaching into the soil. A common approach is to use timber sleepers joined with steel rods to hold them together.
They are perfect for the disabled gardener, those suffering from arthritis, and the elderly as they can be elevated to a suitable level so that bending over and kneeling will not be necessary.
This type of planting will discourage insects and specific vegetable pathogens that can stay in the soil over winter and planting that same crop in that bed will infect the crop.
Lastly, connect your anchors using a heavy-duty string or twine, creating a grid-like pattern of planting squares. You can see an example of the results of this process in my garden bed here: Square Foot Planting Squares.