Hi Bart....I have two wisterias that I grow as standards in pots. For reference, I am in the Seattle area...zone 8b (rain in winter and spring, bone dry summers, mild temps) . My local nursery and garden "experts" advised me strongly NOT to do this....but I did it anyway :) It has been a resounding success! They have been in these pots for 15 years.

This is wisteria floribunda 'Black Dragon' which is a vigorous cultivar that can grow to 30 feet. The tricks I use to keep it in check are:

-they're planted in very large terracotta, which allows them to get somewhat large (they are about 10-12 feet tall) yet keeps the roots relatively dry, so the growth is checked

-I rarely water them, only when I see the leaves curling up slightly. We have bone dry summers, but they are mild in temp (around 75 degrees). At the height of summer I water them MAYBE once every 10 days (they are growing in part sun)

-I have never fertilized

-They are growing on metal stakes, which are the same ones that were in the nursery pots when I got them. The stakes are around 6 feet tall...the wisteria has formed a woody structure above the top of the stake and that's where the flowering branches grow from

-I have never had to hard prune them...they just don't grow enough to have to do that. I cut off whippy growth when it gets too long, maybe a few times in the summer...it's very minimal

-In late winter, I prune very lightly (there's not much to cut!)

-every year they bloom beautifully!!! I'm so happy I experimented with growing them in pots!

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