It’s been one ridiculously named storm after another lately but last Tuesday’s dry (though extremely windy) weather gave me a pleasant window of opportunity for wisteria pruning *insert smiley face here*.

Wisterias are deciduous, twining climbers which produce pendulous racemes of ?owers in pastel shades of purple, pink and white. Of the handful of recognised species, the most commonly grown are Wisteria ?oribunda (Japanese wisteria) and Wisteria sinensis (Chinese wisteria) - but which is which? The stems of W. ?oribunda twine clockwise while those of W. sinensis twine anti-clockwise. Wisteria ?oribunda produces its ?owers and leaves simultaneously whereas the ?owers of Wisteria sinensis are borne on bare stems, before the leaves appear. The pendulous racemes of W. ?oribunda are significantly longer than its Chinese cousin, making it a good choice for archways and pergolas but if you want to cover a sunny wall, choose Wisteria sinensis.

Pruning isn’t complicated but it should be carried out properly twice a year for best results. In summer, the current seasons whippy green growth should be cut back, leaving half a dozen leaves. This step will allow sunlight to ripen the wood and promote ?ower bud formation. At this time of year, we shorten the same growths to 2-3 buds to prevent the beautiful ?owers being obscured by leaves. Tie in well placed branches to give good coverage and if necessary, you can cut back hard any long branches that have become problematic. Once your done with the secateurs, give it a good mulch with well rotted manure. In the spring, apply a high potassium feed to encourage the production of ?owers but take care not to overfeed. Wisteria are legumes and as such they ?x nitrogen in their root nodules - too much nitrogen will stimulate lots of leafy green growth at the expense of ?owers. And if it’s not ?owering its no fun!

My wisteria top tips:

When buying Wisteria, choose one that has been grafted and in ?ower if possible. Look and feel the base of the stem - if there is a noticeable bulge here, its been grafted. Wisterias raised from seed are notoriously slow to ?ower. In some cases you could be waiting decades for a glimpse of violet!

Before investing in this long lived climber, think carefully of where you’re going to put it. They need a warm sunny, south facing, preferably sheltered position on a well drained, moist soil. Their thick woody stems can make them tricky to move if you change your mind regarding their location in your garden so choose its home wisely!