The vegetable beds in the rear garden are divided by double oblique cordons (all semi-dwarfing trees on Quince A/M 26), and fronted by M27 apple step-overs. I've found this has worked very well so far, and vegetable crops do quite well up to about a foot away from the trees (which are essentially root pruned by annual bed digging). One initial worry was that regular manuring of the beds might cause soft, disease-prone growth of the trees, but again this doesn't appear to be a problem.
