About 20 years ago our japanese wisteria died back (There was a hole caused by drainage in the ground by the roots) A little shoot from the base of the trunk survived and I had it in a pot for years.. put it in the ground last year and it is growing more now, but no flowers. I checked the way it was climbing and it is clockwise, so is is a japaenese, but a friend told me it could have me grafted onto a non-flowereing wild variety... Is this a common practice..
Yes. Some Wisterias are grafted when you get them from a commercial supplier. You may well be growing the rootstock. Apart from that, I concluded years ago Wisterias need to be abused - don't fertilize, prune hard and don't water them. I would be interested to hear Ron's comments....
