A Wisteria is a magnificent sight when in full bloom, but unfortunately there are times when it refuses to perform. The problem can be the result of giving the vine too much nitrogen. Four other reasons are also suggested in an article by Heather Rhoades which I found on the Gardening Know How website.

Wisteria is a vine that is well known for its vigorous growth and are just as notorious for being reluctant to bloom. When a wisteria won?t bloom, many gardeners get frustrated and ask, ?Why is my wisteria not blooming and what is the secret on how to get wisteria to bloom?? There is no secret to fixing wisteria blooming problems. A little knowledge can help you quickly fix the problem. Let?s take a look at what you need to do to understand how to get a wisteria to flower.
Reasons Why a Wisteria Won?t Bloom

The most likely reason your wisteria won?t bloom is due to too much nitrogen. When a wisteria plant has too much nitrogen, it will have plenty of foliage growth, but very little and maybe no blooms.

Another reason for wisteria blooming problems is the environment they are growing in. Wisteria vines that lack full sun or proper drainage may be stressed, and while they will grow leaves, they will not bloom. Improper fertilization may also be the answer to the question of why is my wisteria not blooming. Fertilizing in the spring can encourage leaf growth and discourage blooms.

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