@CELIA2 - one of my hardy fuchsias was exactly the same, after checking the roots for weevils, etc, everything was fine but it still grew very slowly the same 2 leaves were there for about a month. Then all of a sudden it's shot up. My point is that sometimes there is nothing wrong it's just the plants decision.
Another thing to check would be is it in full sun, shade, etc. If mostly in shade this could be why.