Pruning Wisteria – ensure a feast of flowers!

My home is something of a cottage cliche. Made of Cotswold stone, roses around the door, low ceilings, flagstone floors, old wooden doors and… wisteria. While I’m not very good at cleaning the flagstones or polishing the wood, I’m much better with the plants. That’s why one of my key gardening jobs for this time of year has to be pruning the wisteria.

Wisteria is a gorgeous, deciduous climber. It flowers in May and June and while it’s in bloom it’s breathtaking. Long, fragrant flowers almost drip from the plant, which itself develops a substantial twisting trunk.

Once the blooming is over, I think the wisteria is still very attractive. It cloaks the house in its frothy green leaves which turn yellow in Autumn, until it loses them in Winter.

There are many types of wisteria but the two main ones are the Chinese Wisteria sinensis and the one we have, Japanese Wisteria floribunda . It’s a bit less vigorous than its Chinese counterpart so less likely to cause a problem growing on a building. And given my home is just a little cottage, it seemed the sensible choice. That said, my wisteria still routinely needs taming and now’s the time to do it!

Pruning Wisteria – why, when and how

Wisteria is an incredibly vigorous climber, putting on metres of growth in a season. In the wild it scrambles through trees to reach the light. So if you don’t prune it, it really will take over. Left to its own devices it will also grow in an awful jumble, and you’ll end up with all the leaves obscuring the flowers. Pruning wisteria also helps encourage short growth packed with flowering buds. In short, pruning wisteria is a must.

Pruning wisteria is really easy theoretically, but practically it’s a bit of a task, especially if you’re short like me – and the wild wisteria is all over your house!

7 Easy Steps

• When – the first prune is in Summer, July or August
• Simply trace each long shoot of new wispy growth back to the base
• Then count along the length of new growth for five buds (leaves)
• Cut after the fifth bud
• Cut at an angle in the direction that the fifth leaf is growing
• If you see long stems with old seed pods on them, cut those stems off too, to keep things looking tidy
• Stick the green leafy prunings into your compost heap, they’ll rot down quickly

Pruning Wisteria – the second prune

The second prune is in Winter (January or February), when the plant is dormant. Again you go to the same shoots, but this time you cut back to three buds. That’s it!

When doing this second prune, all the leaves are gone, so you have a much clearer view of your plant, and its framework structure. This means you can do a general tidy up of your established plant at this time too. Snip off dead bits, or trim back old branches that might have become a bit unruly and risk obscuring the flowering elements.

Obviously if your wisteria is young and you are still training it (we have ours trained across wires on the front of our house) then you will want to train the long young growth rather than chopping it off – to create the basic framework.

Tackling a Takeover!

I’m reliably informed that wisteria is very hard to kill so don’t panic if like me you get it wrong. Mine is absolutely thriving and until a few years ago I didn’t have a clue what I was doing on the pruning front!

It really is pretty bullet proof. Indeed for two of my sons, Angus and Henry, whose bedrooms are at the front, it’s thriving so much that it’s a positive nuissance. It’s climbing into their bedrooms! So in addition to the above technical chop I also tidy things up a bit around their windows.

However, yesterday when I tackled our wisteria, I had to tread a bit carefully when dealing with Henry’s room on the right, as I had a very nervous pigeon on a nest in the wisteria just below me! I don’t know why I was surprised since wisteria is one of my top plants for attracting birds. Once mummy pigeon has finished producing yet another pesky pigeon for my garden, I’ll go back to his room and give the window area a further tidy up.

Beyond the window area, I also have a serious number of shoots growing above the roof line. I didn’t manage to get to these yesterday, and it’s a bit wet and windy today. So it’s a job for later this week. I can suffer from vertigo, making me possibly not the best person for that job! Thankfully, I think Mr F-W is going to ride to my rescue. He’s itching to check the wisteria isn’t going under the slates or messing with our guttering – so to be honest he didn’t take much asking!

Wisteria – planting ideas

Our wisteria is growing over the front of our cottage, mingling with the rose Zephirine Drouhin. Indeed it’s one of my favourite colour combinations. And growing it over the front of a house is perhaps the most popular choice, but there are lots of other ways to grow wisteria.

You can have wisteria cloaking garden walls and framing arches or climbing through mature trees. I think the flowers hanging down from trees look lovely.

I’ve also seen incredible pergolas smothered in wisteria. Though if you go this route, build your pergola for the task. A wisteria develops a substantial trunks and branches. So when covered in leaves and flowers it’s really heavy.

For this reason, I don’t recommend growing wisteria over fences, unless you’ve put some serious reinforcement into the fence!

If you want to grow a wisteria as a free-standing tree, you can. Simply stake the thick woody stem of the plant to a sturdy post embedded securely in the ground. As it grows you remove the unwanted growth along the trunk, allowing only the top to grow.

Using the same technique, but on a much smaller scale, wisteria can be also be grown in large pots. As an absolute pot fantatic, I’m really tempted to have a go at this.

In Japan, wisteria is even trained onto massive trellises to form blooming tunnels in Spring. I’m not sure many of us have the space or dedication to grow one of these but it does give you a sense of the possibilities – and the beauty!

Whatever you do with them, ideally wisteria want to be in well drained soil in full sun. They will cope with a bit of shade but you’ll get fewer flowers. They absolutely hate heavy waterlogged soil, and will not flower in deep shade. They’re best planted in Autumn or Spring.

Got the Wisteria Pruning Sussed – but no flowers?

Let me end with a few last flowering tips. If your wisteria isn’t flowering very well it could be your wisteria pruning regime isn’t quite right, so do check that. However if you’re pruning correctly it may be your plant is still very young; wisteria can take 5 years to start flowering.

If your wisteria isn’t young and your pruning is top notch check your feeding. Wisteria should be fed in Spring but too much high nitrogen fertiliser will encourage lots of leaves. Instead use a high potash fertiliser, this will encourage flowers. (If you want an easy way to remember which fertiliser is good for flowers, I always think ‘Flower Pot’ – so potash. Well that works for me!)

Last thought, if you’ve got a wisteria with pods and you’re tempted to try to grow a new wisteria from one of the seeds, I really wouldn’t bother. You’ll have a very long wait. They can take 20 years and even then there’s no guarantee you’ll get flowers!!

Happy gardening xx