How to Winter Prune Wisteria

Wisteria Flower

Wisteria is an age-old classic. Belonging to the pea family, it is known for its large, hanging clusters of fragrant pea-like flowers that come in shades of purple, pink, white, and blue, blooming from April – June with sometimes a second flush in August. It’s a vigorous plant that needs regular pruning and training to keep it in check and flowering well, but is well worth the effort.

How to Prune Wisteria

Wisteria needs pruning twice a year. For the best performance from the flowers, a summer (July/August) prune keeps whippy growth short and encourages it to form flower buds rather than green growth.

When pruning, it’s important to remove the side shoots that are growing out of the main stem. During the summer prune you will have shortened the whippy growth to 5-6 buds, now is the time during the winter to prune the shoots further leaving only 2-3 buds on each shoot.

This pruning is done while the plant is dormant and leafless to tidy it up before the growing season starts, ensuring the flowers aren’t obscured by the leaves, Restricting the amount of vegetative growth, and encouraging short, flowering spurs which will result in more flowers. Additionally, it is important to remove any side shoots that are growing from the base of the plant as they will not produce blooms.

Wisteria Pea Like Flowers

Types of Wisteria

Wisteria floribunda has the longest flower ‘bunches’ and is best for structures such as pergolas. Wisteria sinensis is best for walls as the shortish flowering ‘bunches’ are displayed to their advantage. Both species look very similar but to help tell the difference W. floribunda twines clockwise and W. sinensis twines anti-clockwise.

Young Wisteria

When buying a wisteria, always choose one that has been grown from cuttings or by grafting, as seed-raised wisterias flower less reliably and also take longer to come into bloom. You should be able to see the graft union as a bulge near the base of the stem. Named cultivars are almost always grafted whereas species are not. To avoid disappointment, buy your wisteria in flower or from a named cultivar, for example, Wisteria sinensis ‘Amethyst’.

Leave your young wisteria unpruned until it has covered the wall or garden structure and then begin the regular pruning to encourage flowering.

Wisteria Framework After Pruning

Rejuvenating Older Wisteria

With older plants, severe pruning may be needed to remove old, tired growths, or branches growing over windows or protruding outwards from the face of the building. Drastically shortening back long branches, removing sections of older stems to just above a strong young branch or growth shoot lower down, or cutting completely back to a main branch, or even to ground level may be necessary.

Take your time if larger, thicker branches are to be removed and where a branch is twining it may be necessary to trace back and mark it at intervals with string before removing it. The result should be a skeleton framework of reasonably well-spaced branches. Keep checking from the ground to make sure you are achieving this as you go.

A little TLC can go a long way…Which is why we also offer our Aftercare services to gardens which just need a little spruce up and not a full transformation too. You too can take advantage of one of our three Aftercare Packages or if you’re needing something more specific, we can tailor-make a package for you.

So, if your older patio needs a fresh jetwash, replacement grout or your shrubs need a seasonal prune you can simply contact our Aftercare Team on 0333 202 1955.

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