I have a white wisteria that I planted at least 6 years ago, and it has never flowered. It has climbed at least 30 feet up a pine tree and has vines on all the branches. It's trunk is the size of my wrist. Unless there is something that I can do to it to induce flowering, I am going to cut it down.
I have a purple wisteria in another pine that has flowered heavily for 3-4 years.