Answer: This particular Wisteria floribunda or Japanese wisteria variety is said to bloom young, so after six years I would have expected flowering for sure. There are several possibilities for why it has not, so far. One is that you are somehow overfertilizing it with nitrogen. This can sometimes happen if it is planted near a lawn that is heavily fertilized and the plant itself is also fertilized. The nitrogen encourages the vine and foliage to grow at the expense of flowers. You might stop fertilizing altogether for a year or two and see if that helps. You might also be pruning it too hard or not quite at the right time. Here is one of the best wisteria care guides I have seen, to help you trouble shoot.
Good luck with your wisteria!
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