Depending on the variety, many of them don't flower for some years, but all are more likely to flower if pruned and trained properly. Google 'pruning Wisteria' and select the RHS page for guidance on this.

Hi Bamboo, I asked a question a while back why my wisteria didnt have many flowers and I'm pretty certain you advised me to feed it some Sulphate of Potash in the autumn - I think it was you, and funnily enough I found a note in my diary and I've done just that today :-)

Yea, I did say that, DA, I remember it. Did you do it last year, and did it make any difference?

Hi Bamboo. :). I have to confess husband cut it back hard, so no flowers this Spring. It has fully grown again so fingers crossed for next year. Quite fancy getting a W. sinensis if it fails as our current one flowers while in leaf as opposed to before leaf ie Sinensis. Lets hope the Sulphate of potash does it work.