grafting , sort of urgent.

hi folks , what i would like to know is it to late to do a graft , the thing is i have a mandarin tree first fruit last year but all on one side of the tree which is the bit that was originally grafted on to the root stock now have been having a good look at it and it looks like its going to fruit again all down one side so im hoping to  graft a lemon on the baron side , there are very small buds apaering and there are loads of new leaves , hope you can help
chrissie b

If you want more branches on the bald side, look for a tiny nub on that side which could be a potential branch. Then with a sharp knife, cut a tiny triangular patch out of the bark just below that bud (wide part at the top of the cut, narrow end at the bottom). You need to go into the green part, but only just. This will will force the hormones that stop more branching to go around this area and allow that bud bit to start branching.