|What size should the frames of a raised bed garden be...2x6, 2x8 or 4x8? 4x8 seems to be appropriate to me. Please note that this is for my personal back yard to grow veggies for my family.
|Do you mean the bed itself, measured in feet? Or do you mean the measurements of the pieces of wood themselves in inches?
If it's the size of the completed garden, that's a personal preference. Remember that one of the main purposes of raised beds is that you do NOT step into them. Therefore the 4' x8' would seem quite appropriate. A bed two feed wide is quite narrow.
If you are talking about the size of the lumber, my personal experience would lead me toward the 4" x 8" as well. It will give stability to the sides of your raised bed, while at the same time being high enough to actually RAISE the bed. A 2" x 8" would work as well, but you might need to add some supports to keep it from collapsing.
One reminder: I would caution you against using pressure-treated wood to construct raised beds for a food garden. Or at least read up on the various literature citing the hazards, and what you can do to minimize them.