Wisterias are a bit of a passion for us, we have several around the garden. Looking really lovely now are the really long racemes (more than 1m, showing off now) of one I bought as Macrobotrytis (sp?) but I believe has been renamed something else? The overall effect is soft and filigree, the colour gentle. The white one has the best scent, it is almost overpowering about now, early evening.
Peter prunes them all back really hard, to 2 or 3 buds in January or February, leaving an almost scupltural framework of branches tied to strong wires. He has another prune in summer to keep it under control - these are vigorous plants to say the least so he ends up with a big pile of trimmings. My contribution is to throw a few spades of bonfire ash on as a mulch in early spring to encourage bud formation and to sit under them when in flower, appreciate their loveliness and drink wine, all these things I have a lot of experience of.