Award-winning gardener Jane Moore, shares her simple step-by-step guide to pruning wisteria, the most spectacular of spring bloomers.
Who doesn’t love a Wisteria, festooned in delicate sky-blue blooms, sometimes wafting a bewitching scent over your patio in spring? The key to all that fabulous flower is ruthless pruning twice a year, and the best time to be tough is in the deep, dark depths of winter. The second pruning? Well, realistically, a summer pruning mainly consists of trying to keep your Wisteria vines actually contained within your garden!
So, the winter pruning is the one that it’s vitally important to get right or you simply won’t get the flowers you hope for in spring. But, this is one of those pruning jobs that can be mystifying for many people, so read on for my five-step plan to getting more flowers and how to best maintain your Wisteria plant this spring.
Get More Flowers on Your Wisteria
Wisteria is a big, vigorous growing plant and there is little that you can do to curb its enthusiasm in the summer, so don’t be afraid to get tough now. Take a big swig of tea, roll up your sleeves and get stuck in. You will need:
Once the leaves are off in January, you can see the shape of the plant. You’re aiming for a framework of branches trained from the main Wisteria plant and tied in to a wire frame on your wall.
You may need to add wires as it grows taller, but you can ‘stop’ your Wisteria plant from growing beyond its allotted space by snipping off the growing point once it reaches the height you’re happy with.
Just so you know, Wisterias tend to die back in sections, even in the very best of circumstances without any particular reason. If that happens, this is a good time to prune off any dead growth – you can spot a dead part easily as it has a grey, brittle look and will snap easily. Once you’ve done that you can select a new stem to replace it from the many that will be available and tie it in to maintain the shape.
Tie in the branches along the wires making sure they’re secure. Try to avoid using wire or plastic ties if you can possibly help it, as these will dig in to the stem as it grows, effectively cutting off circulation of nutrients and water and weakening it so it might die back.
Wisteria is very amenable to being trained, but you do have to be firm. Any vigorous new shoots that spring up outside this framework (and they sure will!) should be cut off back to the main trunk.
Once you have a clean framework, work your way along each of the branches, cutting back the long, trailing shoots to three or four of the pointy black buds. Look at these shoots and you’ll see there’s a cluster of buds near the base of the stem, but these get further and further apart as the stem stretches out. You want to keep that little cluster of buds and create flowering spurs much like you create fruiting spurs on a wall-trained apple tree.
Take a step back and survey your handiwork. Is it looking tidy and uncluttered? Is that tangle of twisting Wisteria stems when you started now a distant memory?
If not, go back in and get some more pruning done. Remember that your Wisteria will throw out a billion new shoots in the summer and they’ll be trailing over the patio, into the trees and up the neighbour’s drainpipe before you know it.
Don’t worry about being tough; a good, hard prune is just what your Wisteria needs to thrive. So be brave and go for it.
Have you pruned your Wisteria before? When do you normally prune your Wisteria? Let us know if you have any questions about pruning Wisteria in the comments.