Answer: If this wisteria was grown from seed rather than grafted, it may simply be too immature to flower. (Sometimes these vines can take 20 years.) Other possible causes for lack of blooms can be overfertilizing with nitrogen and improper pruning. (Lack of sun is another, but six hours of afternoon sun including noon should be enough.) Here is a care sheet to help you troubleshoot.
I hope it blooms for you soon!
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