When I was a kid, my mother always seemed mad, or extremely frustrated, with this one plant she had that would not bloom. It was a wisteria and she wanted so badly for it to cover her fence and bloom those beautiful purple flowers. But as I recall, it never did, and eventually she dug it up.
Back then, I had no idea why. But now that I think about it, along with access to internet research, I think I know why it never bloomed. I’m almost positive she had a Chinese species of wisteria. These and the Japanese species are notorious for not blooming for sometimes five years or more after planting. That’s a long time to wait for a flower, don’t you think?
For some folks though, the end justifies the means, and many will wait it out to get the beautiful blooms. There are some helpful hints that may help along the wait, for those committed to this variety.
First, make sure it is planted in full sun. It can tolerate some shade but full sun gives you the best opportunity for blooming success. If you think it is getting too much shade, transplant it when it is dormant.
Next, prune it back. The process of removing old wood stimulates this plant to bloom. You can prune wisteria in the summer after its spring bloom, and up to four times in the winter when it is dormant.
Also, feeding it with a blooming fertilizer, meaning high phosphorous (the middle number), will also give the best chance for blooms. If you put high nitrogen fertilizer on it (the first number), you’ll get foliage and no blooms.
Another more extreme way of pruning is “root pruning.” In an article written by David Beaulieu, he mentions cutting a foot deep into the ground around the wisteria, maybe 3 feet out, to cut some of the underground roots. This is also supposed to stimulate flower production without harming the plant.
Finally, you can always plant smarter by getting the American species of wisteria. There are a few reasons why this may be your best bet.
The American species is quicker blooming. Also, it is more cold hardy and won’t get frost damage as easily as the Eastern varieties. This will help to have a longer-lasting, healthier-blooming plant.
Lastly, ours is less invasive than the Eastern wisterias, which have been put on the invasive species list. You must be a disciplined pruner or the Chinese and Japanese species can grow out of control and take over where you may not want them.
I wish my mom would have known these things, since it would have saved her a lot of needless frustration and wishful thinking.
If we do our homework and plant smart, we will hopefully select the right plant for our expectations and get years of enjoyment from it.