We have tried salt and vinegar on the main plant, with no.
Dec 14, For the best flowering performance, it’s worth pruning your wisteria twice a year – in winter and in summer. Learn how with this video from the RHS and our a. May 17, Pruning wisteria can be done to overgrown wisteria as well. In this case, wisteria trimming can be accomplished by lopping and cutting as much as you want, down to about 3 feet (1 m.) below where you really want the wisteria to be. This way, as new shoots pop up and it grows to that height, you will get nice new shoots the following spring.