|My wisteria fails to bloom no matter what I do. What is the best way to prune it to encourage flowers?|
|Wisteria is so stubborn! You are in very good company -- you would be amazed at how many folks have difficulty getting wisteria to produce flowers. You are right though, proper pruning can help achieve your goal.
A few other tips to keep in mind: Remember that wisteria needs full sun, and if you have an unnamed seedling rather than a grafted variety, it may take decades to achieve bloom! When fertilizing wisteria, be careful not to use a high-nitrogen type, which can encourage the growth of foliage at the expense of flowers.
Now, for the pruning: All through the summer, prune out the tips of all new shoots when they reach 12" long. In the winter, shorten the shoots again so that about 6 buds remain on each shoot. Cut away all suckers that appear at the base of the plant.
Sometimes root pruning around the drip line of the vine will stimulate the flowers to form for next year. Just dig down one foot deep all around the drip line, breaking any roots you meet. Give these these methods a try!