we live in IOWA and about 5 years ago I planted a Wisteria tree. I keep pruning the long thin branches back and have it growning along a privicy frence and over a patio area. Our problem is that the Wisteria has not bloomed at all. I have not noticed any buds on it anywhere at any time, It's very healthy and quite a grower. I know that I must be doing something wrong, and need help in getting the blooms to sprout. Any and all help will be greatly followed. The shade is nice, but I want the blooms also.