Hi Brendan, I happened on your question and see that you have no replies. I cant tell you what is wrong with your Wisteria (I just planted my first one this year) but I know you will likely get a response if you copy and paste your question on to the "Ask a question" forum.
http://garden.org/forums/view/...
Hope you can save your plant, especially since it's your only white one!
Terri
