There are very few sights that are more arresting than a wall or archway covered with a trailing wisteria in full bloom. However, the climber has a reputation for being tricky to grow, so many of us set aside our romantic dreams of a wisteria-covered home. But while wisteria might need to be pruned regularly, they’re otherwise easy to grow and will be happy in most gardens. They can even be trained as a freestanding plant or grown in a pot.
There’s a surprising number of varieties available in shades of purple, white and pink, with different degrees of fragrance.
Which? Gardening magazine rated 15 commonly available varieties of wisteria to find the best for our gardens. To discover our recommendations, subscribe online to Which? Gardening or call 029 2267 0000.
Choosing the best plant
Buy plants in flower if possible to guarantee you have the variety you want. The National Collection holder in Cumbria recommends The Laurels Nursery in Kent, which can provide plants via mail order. Look for a plant that isn’t suckering from the bottom.
Growing wisteria in pots
Pot wisteria with five parts Best Buy compost for containers and two parts horticultural grit. Feed with sulphate of potash after flowering, and again in August, as the plant is setting the flower buds for the following year.
The wisteria will need repotting every two years into a larger pot unless you prune the roots to keep the plant in a bonsai fashion. Choose a pot that is widest at the neck so removing and replacing the plant is easy.
Growing wisteria in the ground
Plants will dry out quickly, especially in a light or sandy soil, so keep them well-watered, particularly when newly planted and during dry periods. Avoid growing them very close to a wall where it’s very dry.
Training wisteria as a freestanding plant
The stems of wisteria can be trained around each other or given initial support until they are thick enough to stand on their own. Start with a young, single-stemmed plant and train the stem up the support. Remove the tip the following February to encourage side-shoots.
Cutting back whippy stems that grow to the side allows them to develop into woodier stems that can support further flowering stems. Shorten them to around 15cm after flowering in July or August and repeat in late winter until the plant’s shape is established.
Wisteria can quickly get messy. They flower from old wood so if they have too much young, whippy growth you’ll get a poor display so prune regularly. Prune in mid or late summer to reduce the length of young, whippy shoots produced that year so each is left with five to seven sets of leaves – this will
allow them to mature in time for autumn.
Caption: Prune whippy growth in summer
You should then cut back the same stems in late winter so that you’re left with stubby spurs with just two buds each. These should sprout and flower the following spring.
Caption: Cut back the stems you pruned in summer again in winter
Training climbing plants
Wisterias climb by wrapping their twining stems around whatever is nearby. They can’t attach themselves to flat, vertical surfaces, such as walls and fences, so if this is where you want to grow them, you’ll need to
provide something they can grab hold of.
Horizontal wires are the best option as they’re flexible and discreet. Position them 30cm apart and secure using screw eyes on wooden surfaces or vine eyes on masonry.
Wisterias look best when their side branches are trained horizontally so flowers hang more freely. Do this in winter. Secure the main stem vertically, shorten it to 75-90cm and remove any other growth. As new side-shoots appear in summer, tie them in at an angle of 45 degrees against your wires. In subsequent winters, shorten these stems by a third and retie them horizontally. Do this yearly, until you have an attractive framework of branches. From then on, only prune to keep stragglers at bay.
Watch out for wisteria scale, which are brown, shell-like creatures found on wisteria stems.
Caption: Watch out for wisteria scale on the stems