Knowledgebase

Wysteria trouble #927089

Asked March 30, 2026, 3:06 PM EDT

My wysteria didn't bloom last year. It is very unruly and on a 12' high trellised fence. It is very old. When I moved here in 1986 there were seven wysteria trunks spaced out along a 50 yard long fence. The trunks were 8" to 20" diameter but all were rotten with a million suckers coming up around each dead trunk. I tore out the rotten trunks and cut back suckers to the largest two or 3 each. All the years since I trim it back when it gets in trees or starts to reach the house, but last year it didn't flower. I was worried about it and after admiring so many other wysteria in beautiful gardens I was hoping to get someone to come out and help me with mine and get it in good shape. I hired "a specialist" who came over a couple weeks ago. (I found him from Eagle Rock Gardens where he had just pruned a wysteria there). His fee $100 the first hour and $65 an following hours was high but I decided I needed a specialist and figured I had found one. He looked at it and told me to feed it with "flowering-bush granuals and water them in" (I didn't find at the store) and told me "don't touch it for a year". Since I already only touch it when it gets out of control I found the information very unsatisfactory. I think I need someone who knows even more and thought I should trim it after it blooms (and I do see some possible blossoms starting). Do you know when it should be trimmed and exactly what kind of fertilizers I should be looking for? If you know of any possible place for me to look for experienced trimmers of wysteria, I would love to hire someone who will attack it when the time is right. Thanks so much for reading and answering, Debie

Multnomah County Oregon

Expert Response

HI Debie, 
Thank you for using Ask Extension.

I think you will find it difficult to find a wisteria 'expert', but you can become your own expert.  I'm going to recommend you look up the reference book by Brickell and Joyce, Pruning and Training  I have this reference and it goes into detail about training and pruning a wisteria.

Typically, you need to prune twice per year, in the winter to maintain the structure and summer about two months after flowering.  

Generally wisteria don't need a lot of fertilization since they are relatively vigorous, but high nitrogen fertilizers will promote leafy growth.  You may want to have a soil test done to check the fertility of your soil.  The recommendation for a 'flowering fertilizer' means the formula has lower nitrogen than phosphorous or potassium.  I found this OSU article that helps explain how fertilizers are labeled and when and how to fertilize.

Fertilizing your garden: Vegetables, fruits and ornamentals | OSU Extension Service
Regards and happy gardening! Replied March 31, 2026, 3:20 PM EDT

Loading ...