Thanks for all your advice. I have made the decision to give it a good cut. Was going to do it yesterday, but the heavens opened so will have to wait for the next fine day. Would have been good today as the weather was fab, only I had to go to work!! Trust the good old British weather!
@Dewy - I remember planting my passion flower a few years back (it was given to me by my mother-in-law) and at the time wasn't very impressed as it didn't do much, but I kept my patience and finally after two summers it flowered and look great along the trellis at the bottom of my garden. I think it just needs tender loving care 