Posted: 06/08/2016 at 15:27
If it's grafted, it looks to be just above soil level. If you want to train it up wires attached to the wall, I would prune it where the straight red lines are, below. This will remove the section which is growing away from the wall (and which already may be damaged where the red circle is) and leaves a couple of branches, one of which will become the new main stem. The growth along the soil at the bottom may be from below the graft so remove that too.