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.
How can wisteria be stopped from spreading?
So how can you get rid of wisteria after it has grown too much? Wisteria removal might be difficult, but there are various methods you can try. Start by manually picking or digging up any sproutlings. To stop the wisteria from resprouting, cut it to the ground. All wisteria branches (and seed pods) should be bagged up and disposed of to prevent the possibility of new sprouts appearing elsewhere. Then, for permanent wisteria eradication, apply a properly formulated herbicide, such as a non-selective kind.
To the stump, paint or immediately apply the pesticide. You might wish to re-treat them if more sprouts appear in the future. Spraying the foliage should only be done as a last option to protect surrounding plants.
Before cutting and removing the wisteria vine, some people instead opt to soak the leaves or as much of the vine’s tip as possible in a herbicide solution for around 48 hours. Although the majority of herbicides are intended to target certain plants without damaging other vegetation, you should still exercise caution when using them.
For the correct application, please follow the instructions. The optimum time to apply herbicides to eradicate wisteria is in the late summer or early fall. But removing wisteria is probably simplest in the cold.
You shouldn’t encounter too many issues as long as you know how to prune wisteria on a regular basis to keep it under control. Cutting it down and soaking what’s left in an appropriate herbicide may be your only option if your wisteria has grown out of control or if you simply don’t want it.
Recall that organic methods of control are more environmentally friendly and should only be employed as a last option.
Can wisteria be controlled?
Pruning wisteria twice a year is the best approach to prevent it from growing out of control. After the flowers have faded in the early to mid-summer and when the shoots from this year’s growth begin to look untidy, the first pruning should be done. The goal is to remove undesired shoots or suckers and to keep new development close to the main vine as follows:
- Trim fresh growth shoots to a length of 6 inches.
- Suckers at the roots should be removed.
- Cut off any sprouts that the vine’s main support structure doesn’t require.
Since flowers only appear on one-year-old growth, this pruning strategy not only keeps the vine in a tight shape but also enables the blooms to be seen the following year.
Can you fully prune the wisteria?
If the wisteria plant has a lot of dry, old branches and appears to be highly out of shape, it can be severely pruned back.
In order to renovate the plant, it is occasionally necessary to remove every branch, all the way to the main stem or even to the ground. Your wisterias will be inspired to grow new, robust branches as a result of this severe trimming.
McKenzie cautions that while the growth will be of much superior quality, the wisteria may not blossom for two or three years following a hard cut back.
A new pergola or arch can be created by “hard pruning” in addition to retraining the plant.
Does dwarf wisteria grow?
This kind of wisteria is unique from most others in that it has a compact, nearly dwarf habit and can be easily controlled to a manageable size, making it perfect for covering only a portion of a wall or fence. Plant on healthy, well-drained soil in full sun or part shade for simple maintenance.
Are wisteria plants invasive?
Background In 1916, Chinese wisteria was first made available as an ornamental plant. Despite being weedy and disruptive, it has been widely planted, grown, and is still highly popular in the nursery industry.
Availability and Habitat Chinese wisteria, which is widely distributed in the eastern United States, has been found to be invasive in at least 19 states, ranging from Massachusetts to Texas south to Illinois. Although established vines will survive and propagate in moderate shade, wisteria likes full sun. Vines cling to trees, bushes, and man-made objects. Although it can tolerate a wide range of soil types and moisture levels, it likes deep, loamy soils with good drainage. Common locations for infestations include the edges of forests, the sides of highways, ditches, and right-of-ways.
Ecological Danger The tough, woody vines firmly entwine themselves around the trunks and branches of the host trees and sever the bark, causing death by girdling. On the ground, new vines that grow from seeds or rootstocks produce thickets that smother and shade out native plants and obstruct the growth of natural plant communities. Canopy gaps that result from dying girdled trees allow more light to reach the forest floor. While this might momentarily benefit certain local species, it also encourages wisteria to grow and spread vigorously.
- Plant: a clockwise-climbing, deciduous, woody twining vine with strong, smooth, gray-brown stems that are dusted with tiny white hairs. The diameter of older plants can reach 15 inches or more.
- The leaves are complex, alternating, and have 9–11–7–13 leaflets that are egg-shaped with wavy borders and sharply tapering points.
- Flowers, fruits, and seeds: Prior to the development of leaves, flowering takes place in April. The flowers are lavender to purple, appear in pendulous racemes or clusters 6-8 (up to 12) in long, and mostly open at once. Individual flowers are 0.8-0.9 in. long on 0.6-0.8 in. long stalks (pedicels). The fruits are green to brown velvety seedpods 4-6 in. long, narrowed toward the base with constrictions between the 1-3 flat,
- Spreads vegetatively by creating stolons, which are above-ground stems that develop shoots and roots at irregular intervals, as well as via seed, which in riparian environments can be transported by water.
- Look-alikes include the Japanese and American wisterias (Wisteria frutescens), which have leaves that are 7 to 12 inches long, 9 to 15 leaflets that are all the same size, plane margins, tips that are acute to slightly tapering, smooth bright green above, and slightly milky undersides. They bloom in May after the leaves have expanded, with flower clusters that are 4-6 inches long and not particularly pendulous, and individual flowers that are about 3/4 inches long and
Control and Prevention Cut vines to free trees from the weight and girdling caused by modest infestations. Use a systemic pesticide containing glyphosate or triclopyr on the lower cut stem sections. From a seed, new plants may sprout. Long-term planning is necessary (see Control Options).
What distinguishes a wisteria tree from a wisteria vine?
Do wisteria vines and trees differ from one another? I’ve been looking for a place to buy a tree because I’ve seen photographs. I’m always being pointed toward the vine, though. Any information would be helpful.
“Wisteria is a deciduous twining climber native to China, Japan, and eastern United States; there is no botanical distinction between a Wisteria vine and a Wisteria tree. British Royal Horticultural Society The training and trimming make a difference. The tree form is a wonderful choice for planting Wisteria in a smaller garden because it has a 30-foot growth potential and may be rather aggressive. These two websites demonstrate how to shape a wisteria vine into either the traditional or tree form. There is also a link to instructions on growing wisteria.
How is a wisteria tree kept in check?
More drastic actions are required when wisteria has already taken over the entire area. Here’s how to drastically reduce it or do away with it entirely.
Hard Prune
The term “hard prune” refers to a Wisteria that needs to be severely pruned back. Basically, now is your time to remove all the extra growth and reduce the size of the wisteria.
Use pruners or, if necessary, a saw to trim the Wisteria’s top, get rid of growth from undesirable locations (like on your house or trees), remove stray branches, and reduce the size of the shoots. Also get rid of suckers and dead branches. If you wish to shape your wisteria, a hard prune is a great opportunity to set up the foundation.
Late winter, when wisteria is dormant, is typically the time for rigorous pruning. Even though wisteria is quite hardy, excessive pruning could kill it. To lessen the shock to the plant, gardeners frequently spread out a harsh prune over a few years. After a rigorous prune, you should also anticipate a decline in blooming for a few years. For additional details on hard pruning Wisteria, see our article on pruning.
Getting Rid of Wisteria
It’s possible that you’ve had enough of Wisteria and want to put an end to it. There are four major ways to get rid of wisteria on your property:
- Dig up as much of the root system as you can after cutting it down.
- Cut it down, then pull up all the new growth until the roots are killed.
- Use triclopyr or glyphosate (Roundup) to mist the foliage.
- Once it is reduced to a stump, treat it right away with a potent glyphosate or triclopyr solution.
If you have a huge Wisteria vine (or several), it will take some time and effort to get rid of it, just like it would to get rid of a hazardous weed. Herbicide use may require additional treatments, and all techniques include keeping an eye out for new growth.
The root system is the most difficult to eradicate, and some roots may survive and sprout new shoots despite your best efforts. Being constantly alert for new shoots and dealing with them right away, whether by pulling them up or spraying them, is the key to getting rid of wisteria. Until no new shoots sprout, you’ll need to keep an eye on the plant for two or three growing seasons.
Wisteria should be properly disposed of after being pulled out or cut down to prevent it from setting down new roots and sprouting new growth. Wisteria should not be composted unless it is hot compost.