When to winter prune wisteria — and why pro gardeners say the task is key to flourishing displays next season

Pruning is a crucial step in keeping fast-growing wisteria in check, and knowing when to winter prune wisteria can make all the difference to the plant's health come spring.

If you're familiar with the rules around when to prune wisteria, you'll know it's best to give it a trim not once, but twice each year — and now that winter is in full swing, you can start learning how to prune wisteria properly.

'Wisteria is a vigorous climber that will benefit from pruning twice a year,' explains Hannah Rowson, assistant garden centre manager at J. Parker’s.

But exactly when in winter should you be pruning the plant? We checked in with a panel of trusted garden experts to find out when to winter prune wisteria.

When to winter prune wisteria

Even if you're at the start of your journey and still sussing out how to grow wisteria in pots, your burgeoning plant baby can still benefit from winter pruning — it's on our list of plants you should cut back in winter for a reason.

'Kept unchecked, though, wisteria tendrils can grow 25 feet in one season and are strong enough to rip off shingles and rain gutters, which is why it’s so important to develop a regular pattern of robust pruning,' explain the gardening pros at Wilkinson Sword.

But first, you'll need to know when to prune winter wisteria. Usually, it's at the start of the year, in January or February.

'Winter pruning your wisteria in January or February (when the plant is dormant) doesn't just control growth,' says Andrew O'Donoghue, co-founder of Gardens Revived. 'It also encourages the climber to bloom more vigorously the following year, too.'

Mark Dwelly, head gardener at Audley Villages, agrees, noting that dormancy is key when it comes to winter pruning wisteria.

'When your wisteria is leafless and dormant, it's time for cutting back the shoots you would have pruned earlier in the year, and you can even remove any dead or unwanted branches,' he says.

So, you'll need to add wisteria pruning to your list of jobs to do in the garden in January or February gardening jobs.

Andrew O'Donoghue

RHS-trained gardener Andrew O'Donoghue set up Gardens Revived with his brother, Christopher, in 2018 to create a thriving family business. Together, they have worked on residential gardens, listed buildings and gardens, flower shows and large estates with some exceeding 70 acres — many with historical significance.

What you'll need

• Lopping shears like the Spear & Jackson Razorsharp Telescopic Ratchet Anvil Lopper from Amazon
• A pole saw like the Walensee Pole Saw from Amazon
• Secateurs like the Kent & Stowe Garden Cutting Grey & Black Bypass Secateurs from B&Q

Why does wisteria need to be pruned in winter?

As Andrew mentioned, pruning wisteria in winter will control its spread and improve its flowering potential in spring and summer.

'Cutting back a wisteria can help control its size and shape while encouraging the growth of flower buds,' Mark agrees. 'Pruning this year’s growth back to two to three buds from the base will help the plant to bush out.'

Why? It's all to do with which wood wisteria flowers on.

'Wisteria blooms on old wood, so pruning helps to expose these parts to some much-needed sunlight,' explains Andrew.

'Think about it as if you're tidying up your wisteria before the growing season starts, not to mention making sure all of those big purple blooms won't be hidden by leaves.'

Just be sure to learn how to clean your garden tools properly before you set to work winter pruning your wisteria. It's the best way to keep your plant healthy and thriving.

FAQs

What happens if you don't prune wisteria?

If you own a wisteria plant, you've probably asked it at some point: Is winter pruning wisteria essential?

Well, garden experts seem united in the view that it is. Wisteria grows incredibly quickly, so you'll want to keep it under control to keep it from causing any damage to your property.

'Be sure to prune your wisteria twice a year,' says Andrew from Gardens Revived. 'The summer prune is for shaping your plant, while the winter prune is for maintaining size and encouraging those all-important blooms.'

How do you prune old overgrown wisteria?

For overgrown or extremely woody wisteria, a more ruthless prune may be needed.

Depending on the condition of the wisteria, drastically shortening back long branches, removing sections of an older branch or cutting back to the original branch may be necessary.

Now that you know when to winter prune wisteria, it's time to get outdoors and show your favourite climber some serious TLC.