Raised Garden Bed Designs - When growing vegetables in raised garden beds using the Square Foot Gardening approach, your beds should be sectioned off into one-foot sections called planting squares. A 4x4 foot garden bed, for example, will have 16 planting squares (because there are 16 square feet in a 4x4 bed). A 4x8 foot garden bed will have 32 planting squares. Each planting square has an address used to identify the square.
Among the most straightforward is to utilize letters for amounts and columns for rows while for addressing the methods vary, as well as the square is identified by the mixture of the two. Numbering starts in the upper left corner and proceeds left to right, top to bottom. For instance, planting square A1 is the upper left-hand square (1st column, 1st row), while planting square C4 is the square in the 3rd column and also the 4th row. I have yet to find a commercially available garden bed with an enclosed attribute for marking planting squares off.
I wish somebody would develop a Square Foot Gardening grid which you can insert into a garden bed that is raised to mark off squares, if you wish to work with the Square Foot Gardening approach, but until this is available, you'll need to formulate your own system for marking off squares. Step one will be to compute the measurements on the interior of the garden bed, which can be width and the length which is truly usable for planting.
But when you join the planks at the corners, you lose a number of inches, or so the interior measurements of the garden bed are actually a few inches short of the advertised size. In my instance, my beds have an interior measurement of 46.25 inches x 94 inches. I refer to these measurements as Usable Length for the rest of the post.