Wisteria trellis: how to train wisteria to climb up a pergola & other supports

Wisterias are stunning climbers and can grow to impressive heights. Read on to learn how to train a wisteria so it looks its best when its gorgeous, cascading flowers arrive.

Wisteria is a group of deciduous and vigorous climbers that originate from parts of Asia and the United States. Among the several wisteria species available, the Japanese wisteria (Wisteria floribunda) and the Chinese wisteria (Wisteria sinensis) are perhaps the most well-known. However, unlike some other climbers, wisterias do not attach themselves to objects and require support or a climbing aid.

Wisteria trellises and pergolas: is supporting wisteria necessary?

With their vigorous and twining growth, wisteria require support to not only keep them under control, but also to help showcase their blooms come early summer. Wisteria varieties can range in size from around 3m to over 20m tall, meaning that all but the smallest wisterias trained as a half-standard need support of some kind. With their forceful woody vines reaching both high and wide, it is important to grow them in the right place to avoid any structural issues as they mature.

Pruning wisteria is key to their maintenance. It not only encourages bud and flower production, but can also help keep the strong growth in check. That said, some wisteria species tend to be slightly less vigorous than others and can be a wiser choice in smaller spaces. Out of the wisteria species you can choose to grow, the Chinese wisteria is possibly the most vigorous. The American wisteria, especially Wisteria frutescens ‘Amethyst Falls’, is less vigorous and is even suitable for growing in a large container.

Training wisteria: what types of supports can be used?

To bloom well, wisterias need ample room and a location that receives full sun — a south-facing spot is ideal. Training a wisteria to create a framework can take several years. Unless you are growing your wisteria as a standard, it involves encouraging the leading shoots vertically and the lateral shoots that bloom horizontally. Over time, wisterias can produce strong, thick woody stems and cause unwanted damage to structures such as drain pipes or roof tiles. To support these plants, you can use a wisteria trellis or wisteria pergolas, archways and even walls. Many wisterias are trained up the front of houses and look spectacular when in flower. However, you may want to consider growing a wisteria away from a house unless you are able to regularly prune it to prevent the shoots from clambering over windows and roofs.

Wisteria pergola

A wisteria pergola is a wonderful way of showcasing a wisteria, as the pendant flowers hang down through the roof and can be enjoyed from below. Furthermore, with its leafy growth, a wisteria can provide valuable shade to sit under during the summer months. Nevertheless, any wisteria pergola must be sturdy and robust enough to support the weight of the climber when fully grown.

To train a wisteria over a pergola, plant it outside the base of a vertical post, around 20cm from the structure itself. Depending on the variety, wisterias climb clockwise or anti-clockwise but are not self-clinging. To train the wisteria upwards, loosely tie the upright stems to steel wires installed on vine eyes on the post. Once the vertical shoots reach the pergola roof, prune the tips back to just above a bud to encourage them to branch. As the horizontal branching stems grow, tie them over the crossbeams so they eventually cover the entire structure.

As the wisteria matures and becomes self-supporting, remove the ties to prevent them from strangling the stems as they thicken. Prune your pergola wisteria twice a year in late winter and late summer — typically around February and August — to keep the growth in check and to promote flowering.

Wisteria on house

If you want to grow a wisteria on a house, the south or west-facing facades are usually best as they receive the most sunlight. Training and growing a climbing wisteria on the wall of a house requires some forethought, but it is well worth the effort. To prevent a wisteria from damaging a house, you can train it vertically and then as an espalier onto horizontal wires installed at 30cm to 50cm intervals in the direction you would like it to grow. Due to the strength and weight of the wisteria when fully grown, the wires should be made of steel and held between wire tensioners attached to vine eyes firmly attached to the wall. As with a wisteria pergola, tie in the shoots to the wires to create a framework and remove the ties when the branches no longer need support.

Due to the potential structural damage that a wisteria can cause, it is vital that you strictly adhere to the bi-annual pruning previously mentioned. That said, it is also wise to regularly check the wisteria’s growth and prune away any unwanted growth to protect any drain pipes, windows and roof coverings.

Wisteria on arches

Training a wisteria over an arch can create a stunning entrance or garden feature. However, as with any wisteria support, the arch structure needs to be able to support it when fully grown. When training a wisteria on an arch, plant the wisteria on the outside of the base so as not to reduce the space within. Train the vertical shoots up the side of the arch, tying them in loosely to the arch using flexible wire. It is inadvisable to allow the shoots to twine around the arch itself, as they may damage the structure when they mature. Once the shoots reach the top of the arch, prune the stems to encourage lateral growth. In time, these will cover the top of the archway and produce buds and subsequent flowers.

When choosing a wisteria to grow on an arch, opt for a wisteria variety that will grow to the appropriate size. Smaller arches may warrant one of the less vigorous species, whereas for long tunnels you may need to plant more than one wisteria to cover it.

Wisteria on fence

Due to their size and weight when mature, wisterias are not commonly grown along wooden fences. This is because wooden fences may not be strong enough and might also need replacing in the future. However, you could train a wisteria along a metal fence or a railing if it is structurally secure. To prevent any long-term damage, tie in the wisteria shoots using wire to run alongside the fence rather than twine within. To train a wisteria on a fence, tie it in vertically until it has reached the desired height before guiding the branches horizontally where they are to flower.

Although beautiful when in bloom, wisteria can also be harmful. You can discover if wisteria is poisonous in our separate article.