Answer: Since it was in bloom when you bought it then you know it is capable of blooming, that is a good thing. Wisteria may fail to bloom if it is growing in too much shade, if it is pruned incorrectly, or if it is overfertilized with nitrogen. Too, most vines take about three years to settle in and become established and perform their best. But when everything has been done right and it still doesn't bloom, sometimes it is due to being located in a colder microclimate -- an exposed spot or even a frost pocket -- where spring frosts frequently damage the buds. Here is a general care sheet on wisteria, perhaps it will help you trouble shoot. It also includes detailed training and pruning instructions along with fertilization recommendations.
Good luck with your wisteria.
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