Regularly Evergreen Garden Works has rooted cuttings of named Wisteria cultivars. You gain a year or two on size over seed, and you gain a decade or more, in waiting for the first bloom. Wisteria from seed tend to not flower until the vine is older than 10 years. I waited 15 years for a seedling I planted in the ground, then when it bloomed it was a yawner, a very generic boring wisteria with bland colors. If you want wisteria, buy rooted cuttings (not grafts)