Ten foot 3/4" electrical conduit driven four feet into the ground has worked for me on B9 and M26. I slip a PVC Tee fitting over the top end and run twine through that to support limbs that need it. I use an electric engraver to write the scion and rootstock names, the transplant date, and the nursery on a scrap of aluminum flashing and fasten that to the conduit with a radiator-hose clamp. I use square-link plant ties to secure the trunk at about three places.