How To Build A Wisteria Pergola

One of the most fanciful flowering plants is wisteria, which blooms every spring with stunning purple and blue blossoms that hang like bunches of grapes. This fast-growing vine is perfect for climbing on pergolas and other buildings, but if sufficient care and maintenance aren’t given to it, it could become out of control.

You must make sure your pergola is a strong, solid framework if you want to grow Wisteria on it. Wisteria can be trained to climb the pergola and then pruned to promote side sprouts. Wisteria is simple to grow and plant, however certain types work better for pergolas than others.

What types you should think about, how to grow Wisteria on a pergola, and how to take care of and preserve your vine are all covered in this post. I’ll also offer some suggestions for pergolas that can support your wisteria while still being aesthetically pleasing.

How is wisteria trained to grow on a pergola?

My initial apartment search in Brooklyn led me to a one bedroom on a peaceful, tree-lined street. The apartment wasn’t particularly noteworthy, but the structure was: The entire brownstone, windows and all, was covered in an impenetrable mass of wisteria. Some strong wisteria vines, which may grow 10 feet or more in a single season, can easily cover a three-story building. Despite its rambunctious nature, a wisteria in full blossom is one of the most beautiful views.

Wisteria may happily twine, climb, and sprawl over anything in its path for a very long time without any pruning. But a trimming routine becomes an essential task for the gardener who has a small yard and wants to enjoy more obvious and many wisteria flowers. Plan on pruning at least twice a year (once in the summer and once in the winter) for best results. Understanding how the vine develops will also help you succeed.

Not everyone prefers to live without windows, but no one needs to if they plan ahead and make a commitment to routine pruning.

Summer: Cut the long shoots after flowers fade

Since wisteria flowers grow on the growth from the previous year, pruning wisterias twice a year not only keeps them in controllable proportions but also develops a network of short branches close to the building so you can more readily enjoy the blooms. Simply cut the long branches from the current year’s growth back to 6 inches in length in the early summer after the vines have flowered to achieve this. Pruning away root suckers, especially on grafted kinds, and totally removing any branches not required for the main framework of the plant should also be done at this time. Depending on how much time you have and how tidy you want your vine to look, you could choose to prune this way once or more regularly during the summer. Remember that wisteria seedpods are ornamental to many gardeners, so you might wish to leave some wasted blossoms remain.

Design Tip

For winter interest, some seedpods may be left on the vine, but if you bring them inside, high temperatures will force them to explode. The pea-shaped fruit was once utilized by a friend as part of a winter arrangement. The following morning, she discovered her cat hiding in a corner from the flying seeds.

Winter: Prune long shoots down to three or five buds

Trim the long stems that have sprouted after the summer trimming to three to five buds in the late winter. Remove any undesired long shoots from the previous season as well; they will be easier to spot now that the framework is leafless.

To focus energy on flower production rather than vegetative development, even short branches should be pruned to three to five buds.

Why your wisteria may not bloom

Wisterias are infamous for not blooming. Make sure these fundamental cultural prerequisites are satisfied before attempting severe measures.

The decision to go with a seed-grown plant rather than a grafted plant is the most frequent cause of a lack of flowers. While seed-grown vines may take up to seven years before flowering, grafted plants normally blossom within three years.

High winds and late frosts can harm flower buds, particularly those of Wisteria sinensis. Wisteria, on the other hand, blooms best following years with hot summers.

Avoid fertilizer with a high nitrogen content. Wisteria fixes nitrogen in the soil like other legumes do. A surplus of nitrogen might result in poor flowering and excessive leaf growth.

Training a new wisteria on a pergola

The plant’s strength allows it to adapt to various forms. Wisteria can be trained against a structure or lattice, molded into a shrub or standard, or planted on a pergola or arbor. Because of its long blossoms, which dangle dramatically through the top of pergolas and arbors, wisteria floribunda is a popular choice. Since it grows so quickly, like other wisteria species, only one plant is typically required to completely cover a structure. However, placing two vines at the opposite ends of a structure provides it aesthetic balance and allows a gardener to showcase two different cultivars on the same structure.

Planning is essential when training wisteria to grow on a pergola or arbor. These constructions must be fashioned of a sturdy, weather-resistant material, such as cedar, and properly anchored in the ground with concrete footings in order to be used effectively. Don’t be scared to overbuild a pergola or arbor because wisteria is notorious for tearing down its supports. I suggest using at least 24 lumber for the crosspieces and 44 lumber for the posts.

Allow two or three young shoots to knot loosely around each other and the post as they grow to start training a new plant onto a pergola or arbor. Since the woody stems grow gnarled and attractive as they mature, this will help give interest to the plant’s structure. As they climb, the young shoots need to be fastened to the post. To do this, fasten a 14-gauge galvanized (or comparable) wire to the post using eye hooks spaced roughly 18 inches apart (or on all four sides for extra support). Use gardening twine to secure the shoots to the wire as they develop. As they develop, give them some breathing room to develop a more attractive habit and avoid having them mature and put a lot of stress on the framework.

The shoots should be headed back (their tips should be pruned) once they have reached the top of the arbor to encourage side shoots that will spread across the tops of the supports and bear flowers. The training ties on the post will no longer be required as the plant matures and becomes more stable across the top of the structure. In order to keep the plant from becoming girdled as it grows, it is a good idea to remove them.

Does wisteria damage pergolas?

Wisteria can definitely grow on your pergola! Wisteria is an aggressive climber that can grow on almost any building. To hold the weight of the plant, however, the pergola must be strong enough. You may then teach your Wisteria to grow in the proper direction.

Your wisteria will completely transform the appearance of your pergola, adding shade and turning it into a gorgeous garden or yard center point. However, if weak buildings aren’t adequately supported and maintained, wisteria can swiftly spiral out of control and engulf them.

Since wisteria is a twining vine, it lacks the sticky clingers that Boston ivy or Virginia creeper can use to cling to objects. Additionally, unlike grape vines or clematis, it lacks stems that resemble grabbers. Wisteria’s twining growth habit means that as it twists upward, it greatly depends on its supporting structures.

When fully grown, wisteria vines can reach lengths of up to 75 to 100 feet and get very heavy. If you keep up with pruning and upkeep, planting wisteria to climb a pergola is an excellent way to keep the plant contained.

Although many Wisteria start to blossom during the first few years, some can take several years to bloom. If it takes at least three seasons before you see flowers, don’t be discouraged; wisteria is worth the wait. If, however, after three to five years, you are still not getting blooms, you might simply have an obstinate plant that is awaiting the right circumstances or is an especially slow bloomer.

Wisteria on a pergola is lovely even without flowers. You will be left with a green, shaded shelter as the twisting vines ascend to the top and form a canopy over it.

Wisteria is a deciduous plant, so each winter it loses its leaf, but even then, the stems and vines still have a whimsical and fantastical appearance. These article contains detailed information on this and other things you might anticipate from your wisteria plant each season.

Which direction should wisteria grow?

Wisterias thrive in full light, fertile soil, and both. Of the 10 species, three are grown the most frequently: Wisteria brachybotrys, Wisteria sinensis, and Wisteria floribunda, which are native to China, Japan, and the eastern United States (silky wisteria). All three species have significant growth rates and can extend out to a maximum of 20 meters (66 feet) against a wall or around 10 meters (33 feet) in trees. Wisteria can also be trained to grow as a free-standing standard in a big container or border.

Wisterias for pergolas and arches

The Japanese wisteria (Wisteria floribunda) is best exhibited hanging down from a garden structure like a pergola or arch since it has the longest flower sprays (or racemes) of all the species. They entwine in a clockwise motion while simultaneously bearing blooms and leaves. Lilac blue blooms and racemes as long as 1.2 meters (4 feet) are produced by Wisteria floribunda f. multijuga AGM in the early summer.

Wisterias for walls

Wisteria sinensis, often known as Chinese wisteria, blooms in the springtime before the leaves do. For example, Wisteria sinensis ‘Amethyst’ AGM has violet blue blooms with a reddish flush produced in dense racemes to 30cm (1ft) long in late spring or early summer. They twine anticlockwise and the racemes are shorter so they are best presented against a wall.

Silky wisteria (Wisteria brachybotrys), which can be grown against walls or on pergolas, with downy leaves and small racemes of 10-15cm (4-6in). White flowers with center yellow markings, a strong perfume, and 10-15 cm tall sprays of wisteria brachybotrys f. albiflora ‘Shiro-kapitan’ AGM bloom in the spring and early summer.

If you want to cultivate a wisteria in a big container

It is best to choose Wisteria fructens ‘Amethyst Falls’ because of its compact habit and rich clusters of lilac-blue blooms.

Always choose a wisteria that has been developed from cuttings or by grafting when purchasing one because seed-raised wisterias flower less consistently and take longer to bloom. The graft union should be seen as a swelling close to the stem’s base. Unlike species, named cultivars are virtually always grafted. Purchase your wisteria in flower or go with a specific cultivar to avoid disappointment.

Wisterias are offered for sale as container-grown plants at garden centers and online, and you can use the RHS Find a Plant tool to locate particular cultivars.

Wisteria should ideally be planted between October and April. Wisterias grown in containers can be planted at any time of the year, but fall and winter are the easiest times to maintain. Give them healthy, well-drained soil to plant in.

Wisterias bloom best in full sun, so pick a wall or pergola that faces south or west. Although blossoming will be diminished, they will still grow in light shade.

Wisterias are robust climbers that can grow to a height and width of more than 10 meters (33 feet). You’ll need to give support in the form of wires, trellises, or outside buildings like pergolas or arches against a wall. Wisteria can also be grown up a support or taught up a tree to create a standard. A wisteria can be grown in a border or container by being trained into a standard, which reduces its vigor.

If you want to grow your wisteria in a container, you’ll need a sizable one that is at least 45 cm (18 in) in diameter and is filled with potting soil with a loam basis, like John Innes No. 3.

Feeding

Use Growmore or Fish, Blood and Bone on your wisteria in the spring at the suggested rate listed on the packet. Additionally, apply sulphate of potash at a rate of 20g per sq m (1/2 oz per sq yard) on sandy soils (which have low potassium levels). Fertilizers for flowering shrubs or roses are another option.

Feed wisteria in containers using Miracle-Gro, Phostrogen, or another comparable flowering plant food. A different option is to add controlled-release fertilizer to the compost.

Although wisteria has a reputation for being challenging to prune, this is untrue. Once you’ve made it a habit to prune your wisteria twice a year, you should be rewarded with a pleasing flower show.

When you prune regularly, you reduce the excessive, whippy growth from July and August to five to six leaves, or roughly 30 cm (1ft). This increases the possibility of blossom buds budding and permits the wood to ripen. Then, in February, trim these shoots even more to two or three buds, or around 10 cm (4 in), to tidy up the plant before the growing season starts and make it possible to observe the new flowers.

When your juvenile wisteria has completely covered a wall or other garden structure, start the routine pruning to promote flowering.

Small gardens benefit greatly from the training of wisteria as a free-standing standard in a border or container.

Wisteria can be trained to ascend into a tiny tree’s canopy, however doing so could eventually harm the tree. Pruning will be challenging if the plant develops into a huge tree, and a dense leaf canopy will affect flowering.

Increase your wisteria stocks by layering in the summer, taking softwood cuttings in the spring to mid-summer, or taking hardwood cuttings in the winter since seed-raised wisteria can take up to 20 years to flower.

Wisteria is typically propagated via grafting in professional nurseries, however layering is the simplest and most dependable technique for home gardeners.

Established wisteria can produce hanging, bean-like seedpods after a lengthy summer. While wisteria plants grown from seeds are typically of inferior quality, you might want to try growing wisteria yourself.

After the leaves have fallen, gather the seedpods and let them ripen in an open tray.
When the seed is ready, twist open the pod and sow it 2 cm (3/4 in) deep in seed compost.
Before planting if the seed is dry, soak it for 24 hours.

See our commonly asked questions page for a summary of wisteria issues.

Poor flowering

Poor flowering is the most frequent issue for backyard gardeners, and it can be brought on by a variety of factors, such as:

Young plants can take up to 20 years to flower, so acquire a plant that is already in bloom or go with a certain cultivar because they are typically grafted to avoid disappointment.
Examine your pruning methods and timing because early and midsummer trimming will prevent the growth of flowers the next year.
Wisteria flowers best in broad light; deep shadow produces few, if any, flowers.
Water your wisteria during periods of drought from July to September because a lack of water during this time will influence the development of flower buds the next year.
Flower buds may drop before opening as a result of spring frosts, which can harm or deform growing flowers.
Applying sulphate of potash in the spring will encourage bloom production for the next year in soils that may lack potassium.
The damage caused by pigeons or mice can be identified by torn petals or distinctive teeth marks.