The 4x8 foot garden beds I bought, for instance, are 4x8 feet from end to end. But when you connect the boards at the corners, you lose a few inches, so the interior dimensions of the garden bed are actually a few inches short of the advertised size. In my case, my beds have an interior dimension of 46.25 inches x 94 inches. I refer to these dimensions as Usable Length for the remainder of this article.
When gardening in these beds only means you are growing your flowers and vegetables above the ground. You can create your own by building a wooden structure with drainage holes in the bottom and fill it with your favorite organic soil mixture. Concrete blocks, bricks, or just about any material strong enough to hold the garden bed and raise it above the ground can be used.
Then, determine what you would like to use for the anchors. If you built your garden bed out of lumber, you could use nails as anchors, spacing each nail the appropriate distance as determined by the results of the calculation in Step 1 above. If your garden bed is made out of a composite material (part wood waste, part plastic), I recommend using an anchor placed on the outside of the bed. Since my beds are 6 inches high, I used 12 inch metal spikes I bought from the local hardware store, pounding them into the soil directly on the outside of the garden bed.
Companion planting is something to consider when planting in your raised vegetable garden beds. Companion herbs and companion vegetables help in the control of insects and will improve the health of the garden.