Hi Paul,
I got my wisteria about 3 years ago in the sickling pile at the nursery. It recovered nicely and is one of my most prolific growers. It was probably about 2-3 years old from the nursery, so I would say its about 6 or 7 years old now. I would like to see what color and length the flowers will be as there was no tag on it. I would prefer long purple blooms like the one you have. Do you know if it is Chinese, Japanese, or American? What is the current age of yours if I may ask? I would also like to obtain about the same trunk diameter of yours before putting it into a bonsai pot.