My wisteria fails to bloom no matter what I do. What is the best way to prune it to encourage flowers?

Wisteria is stubborn, often refusing to produce flowers. But you’re right, pruning may help achieve your goal.

All through the summer, prune out the tips of all new shoots when they reach 12 inches long. In the winter, shorten the shoots again so that about six 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 1 foot deep all around the drip line, breaking any roots you meet.

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.