Based on my observations over the years, I intend to support my newly acquired grapevine with 4" x 2" posts bedded in fine gravel. They always rot at ground level, so maximum drainage for the first 6" or so would seem to be the key to post longevity. Well, at least you can yank them out easily enough when they do rot. Anyone any comments? Metposts are not really approved of by the allotment establishment!