I have a question, I look at the pictures of Wisterias and they have the flowers in "clumbs" mine are single flowers. But I have to say that in Spring the FIRST blooming is pretty full. Then I will get a second blooming not so many flowers. Right now middle of July she has "sprung" a mass of blooms will do this up to 5 times a year when I see other ones around town that only bloom once why is this that mine will have multiple blooming?
There are 3 main wisteria types, Chinese, American and Japanese. They are all a bit different in bloom characteristics. Bloom in wisteria is also affected by how much sun the leaves get, under or over-fertilization and improper pruning. Unlike other shrubs or vines, wisteria can't just be "cut back" to contain growth. Specific cuts back to the "monkey feet" buds stimulate bloom. To be a prolific bloomer, proper pruning in late winter and mid summer is a must. It is quite a chore considering how tall and massive some get. Congrats on taking great care of your wisteria.