When To Plant A Wisteria

In the spring, wisteria blooms ferociously, producing clusters of lilac-colored flowers on fresh growth that develops from spurs off the main stalks. Check out our Wisteria Growing Guide for more information on wisteria maintenance, including planting and pruning.

About Wisteria

Wisteria is a long-living vining shrub with cascades of blue to purple blossoms that, in the spring and early summer, look stunning hanging from a pergola or archway. However, this vine is known to grow fairly heavy and to grow quickly and aggressively, frequently reaching lengths of more than 30 feet. It’s advised not to put wisteria vines too close to your home since they will squirm their way into any crack or crevice they can find.

Beautifully fragrant wisteria flowers offer a feast for the senses. A brown, bean-like pod remains on the plant during the winter after flowering. There are only blooms on fresh growth.

Note: Be careful when planting wisteria! The wisteria plant contains lectin and wisterin, which are poisonous to people, animals, and even pets. If taken in significant quantities, these poisons can result in anything from nausea and diarrhea to death.

Is Wisteria an Invasive Plant?

The wisteria species Wisteria sinensis and Wisteria floribunda, which are not native to North America, are regarded as invasive in several areas. If you want to add a new wisteria to your garden, we advise choosing one of the native North American varieties, such as American wisteria (Wisteria frutescens) or Kentucky wisteria (Wisteria macrostachya), which are excellent alternatives to the Asian species.

Do you want to know how to distinguish between North American and Asian species?

While North American wisteria is not quite as aggressive in its growing tendencies and has smooth seed pods and fruits in addition to more-or-less cylindrical, bean-shaped seeds, Asian wisteria is an aggressive grower with fuzzy seed pods. Another distinction is that the flowers of American and Kentucky wisterias appear in the late spring after the plant has begun to leaf out, whereas those of Chinese wisteria do not.

When to Plant Wisteria

  • Plant during the plant’s dormant season in the spring or fall.
  • Wisteria can be grown from seed, although plants from seeds frequently take many years to mature and begin to bloom. It is advised to buy wisteria plants that are already established or to begin with a cutting.

Where to Plant Wisteria

  • Put a plant in full sun. Even while wisteria will grow in some shade, it won’t likely bloom. Sunlight is necessary.
  • Wisteria should be grown in fertile, wet, but well-draining soil.
  • Wisteria will grow in most soils unless it is in bad condition, in which case you need add compost. Find out more about soil improvements and getting the soil ready for planting.
  • Because wisteria grows swiftly and can easily engulf its neighbors, pick a location apart from other plants.
  • Additionally, wisteria is renowned for encroaching on and infiltrating surrounding buildings like homes, garages, sheds, and so on. We highly advise against growing wisteria too near your house!
  • Wisteria vines need a very strong support, like a metal or wooden trellis or pergola, to climb on. Plan carefully and use substantial materials to construct your structure because mature plants have been known to become so heavy that they destroy their supports.

Wisteria looks gorgeous growing up the side of a house, but use caution when planting it because it is a very strong vine that will get into any crack or gap!

Caring for Wisteria

  • Apply a 2-inch layer of mulch and a layer of compost under the plant each spring to keep moisture in and keep weeds at bay.
  • Phosphorus is often used by gardeners to promote flowering. In the spring, work a few cups of bone meal into the soil. Then, in the fall, add some rock phosphate. Study up on soil amendments.
  • If you get less than an inch of rain each week, water your plants. (To determine how much rain you are receiving, set an empty food can outside and use a measuring stick to gauge the depth of the water.)
  • During the summer, try pruning the out-of-control shoots every two weeks for more blooms.

Pruning Wisteria

  • In the late winter, prune wisteria. Remove at least half of the growth from the previous year, leaving only a few buds on each stem.
  • Also prune in the summer after customary flowering if you prefer a more formal appearance. On fresh growth, spurs from the main shoots of the wisteria develop its blossoms. Trim back every new shoot from this year to a spur, leaving no more than 6 inches of growth. So that there are no free, trailing shoots, the entire plant can be trained, roped in, and otherwise organized throughout this procedure.
  • Mature plants that have been cultivated informally require little to no more pruning. However, for a plant that has been formally trained, side branches should be pruned back in the summer to 6 inches, then again in the winter to 3 buds.
  • Possess you a fresh wisteria? After planting, aggressively prune the vine. Then, the next year, trim the main stem or stems to a height of 3 feet from the growth of the previous year. After the framework has grown to its full size, midsummer extension growth should be cut back to where it started that season.

Which month is ideal for wisteria planting?

The best seasons to plant wisteria are spring or fall, and you should put it in full sunlight to ensure that you get to view its lovely blossoms. A wet, well-draining soil is ideal for wisteria.

Types of wisteria:

There are two varieties of wisteria: Asian and American. Although aggressive growers, Asian wisterias are well-known for their stunning blossoms. American wisterias are less aggressive and still produce beautiful blossoms. Compare the most popular wisteria varieties.

Flower color:

Wisteria comes in a range of colors, such as white, pink, and blue tones, in addition to the well-known purple blossoms. If you believe you have seen a yellow wisteria flower, it was probably a golden chain tree (Laburnum).

Foliage:

Wisterias are deciduous, which means that when the weather becomes chilly in the fall, they lose their leaves. The misunderstanding is occasionally brought on by a different vine known as evergreen wisteria (Millettia reticulata).

Avoid planting aggressive wisterias close to your home as they can cause damage and have even been known to destroy buildings.

Wisterias can be grown in full sun or partial shade, but to promote healthy bloom development, make sure the vines get at least six hours of direct sunlight everyday. If you reside in a colder area, pick a planting location that is protected because a heavy spring frost can harm the flower buds.

Create a planting hole that is the same depth as the plant and twice as wide, then level the plant with the soil surface. Because the vines will soon fill in, you should space your plants at least 10 to 15 feet apart along the support structure.

Wisterias don’t need much care once they are planted to promote healthy growth. Water frequently over the first year until the roots take hold.

After planting, wisterias could take some time to come out of dormancy and might not start to leaf until early summer. They will leaf out at the regular time the following spring, but don’t be surprised if they don’t bloom. Wisterias take three to five years to reach full maturity and may not start blooming until then.

Wisterias grow quickly and can reach heights of up to 10 feet in in one growing season. That works out well if you need to quickly cover a fence or pergola but don’t want the vines to take over your landscape. Regular pruning (once in the summer and once in the winter) not only controls wisteria’s growth but also encourages more robust flowering by creating a framework of horizontal branches and causing spurs to grow at regular intervals.

Cut back the current year’s growth to five or six leaves in July or August, or roughly two months after the plant flowers, to get rid of stray shoots and make short branches that will produce flowers the following year. Summer pruning needs to be done more frequently. Re-prune the plant in January or February while it is dormant by removing two or three buds from the growth from the previous year.

The first few years of wisteria’s growth are crucial for creating the desired framework for the plant’s development. As soon as your wisteria begins to grow, start connecting particular lateral shoots to its support structure. You should also cut down any extra growth. An aggressive pruning may be required on elder plants to promote the growth of new branches. Cut down aging branches to the main primary stem to accomplish this. The spaces will soon be filled with new side branches that can be connected back into the support structure.

Visit the Royal Horticultural Society to view a video on how to prune wisteria vines properly.

Where should a wisteria plant be planted?

According to Kirsten Coffen, a landscape architect and designer based in Maryland, “its gorgeous spring-blooming cascade of purple (or white) scented flowers is best observed when trained on a structure, such as a robust pergola.”

Such a lush, floral canopy offers delightful shade throughout the sweltering summer months. According to Irene Kalina-Jones, a landscape designer at Outside Space NYC (opens in new tab), “We plant it on rooftops in the city, training it to cover pergolas to create shade.” “But I enjoy it grown against buildings, too,” you say.

Wisteria grows best in full sun in a protected location, such as a south or west-facing facade. When planting, work in a lot of organic matter (such as compost) to ensure that the soil is rich and well-drained.

If you want to grow wisteria up a wall or the front of a house, put some effort into building a strong structure that it can climb over many years. A tensioning system of wires is possibly preferable to a wooden trellis because wood can rot. The wires must either automatically tighten as the plant gains weight or be simple for you to tighten (via turnbuckles, for instance).

Where shouldn’t wisteria be grown?

In order to support the massive vine, the wisteria’s root system extends out widely and dives deep. Do wisteria roots exhibit aggression? Yes, wisteria’s root system is highly aggressive. Avoid planting wisteria next to walls or walkways because of its extensive and strong root system. These are easily harmed by a wisteria’s root system.

Experts advise inserting a corrugated panel about 6 feet (1.8 m) long and several feet (1 m) broad beside the plant to redirect the roots if you find a wisteria close to a building or pathway.

Can wisteria grow on a fence?

Wisteria sinensis or W. floribunda are the two species that we grow the most frequently. The former Chinese wisteria bears its flowers prior to the development of its leaves. The blossoms of the Japanese wisteria floribunda develop simultaneously with its foliage. These details have a significant impact on the species you should choose to raise. W. sinensis thrives on vertical surfaces (house walls, fences, trellises), where its bare blossoms will be best seen. It is preferable for W. floribunda to grow up and over strong arches, arbours, and pergolas. As a result, the longer racemes (bunches of flowers) can hang down and be completely free of the leaves.

How to plant wisteria

Wisterias grow best in soil that is fertile but well-drained. Even though they perform best in direct sunlight, they can tolerate little shade. They can be grown in big containers. To prevent a “rain shadow,” make sure plants are 30–40 cm away from the base when growing up a vertical surface (the dry, shaded area closest to the base of walls and fences). Back the shoot up toward the ground.

Wisteria can be grown into a free-standing specimen; more on that later.

Training wisteria as a climber

When preparing Wisteria to climb, there are only four guidelines to remember:

  • In July or August, reduce the whippy shoots from the current year to just five or six leaves. This improves bud formation and speeds up wood ripening by increasing air movement and light penetration through the leaf.
  • In January or February, perform a second cut, only removing two or three buds.
  • Strong, taut training wires positioned horizontally along a wall or fence are used to train desired shoots. Use soft twine to secure shoots to these wires.
  • If it’s necessary to remove old, diseased, or unwanted shoots, wisteria will react nicely to hard pruning. However, be cautious since shoots entwine around one another; you don’t want to unintentionally harm good, productive growth.

Training wisteria as a free-standing specimen

In your garden, grow a few free-standing wisterias for something a little different.

  • Plant a wisteria with a single stem next to a reliable support (1.5m or more). The single stem should be tied in and let to extend all the way to the support’s top.
  • In the first spring after it has reached the peak, cut off the single stem tip.
  • Trim the upper side shoots to 15 to 30 cm in length and remove the lower side shoots. The plant now has a sturdy “head” from which to grow.
  • August is the time to prune August shoots back to seven leaves once the head has gotten sufficiently woody.
  • To keep your shape, trim any old, undesirable head shoots in the winter.
  • To reveal flower racemes, trim March shoots back to 2.5 cm of their bases.

How should wisteria be maintained in the winter?

Make the cut directly above that leaf, then trim them back to five or six leaves from the main branch. Winter pruning: After the summer pruning, long, whippy shoots that grew should also be cut back. Cut these back from the main branch to five or six buds, right above a bud.

Canines are wisteria poisonous?

Because wisteria doesn’t have a bad taste, dogs may eat deadly amounts of it.

Wisterias are absolutely gorgeous, with cascades of flowing purple blossoms. However, their leaves and blooms can also be dangerous in excessive numbers, and their seeds (and seed pods) are extremely poisonous to dogs.

Even worse, the results take time to manifest. Wisteria also doesn’t taste unpleasant, making it simple for dogs to consume excessive amounts before you realize there is a problem.

When does wisteria flower?

A twining, deciduous climbing plant with a long flowering season and fragrant blossoms is called wisteria. When in bloom, a wisteria is a wonderful sight with its long, trailing, fragrant blossoms in blue, purple, pink, or white. Wisteria is typically grown on a south-facing wall. Wisteria is a rewarding plant with lovely flowers that bloom between April and June, and occasionally again in August. While wisteria sinensis twines anticlockwise and is the more vigorous of the two, wisteria floribunda (which twines clockwise) originates originated from Japan. In W. senensis, flowers emerge before foliage, whereas in W. floribunda, flowers and foliage emerge simultaneously.

Wisteria requires a lot of room because it grows quickly, reaching heights of up to 9 meters (30 feet). It can’t stand on its own and needs a framework of wires or supports to develop. Prior to planting Wisteria, it is best to build the structure. Wisteria can survive in light shade as well as full sun, though it prefers the former. The drawback of growing wisteria is that it requires a lot of time and effort to flourish. It has the name “red wheelbarrow plant” on it.

Wisteria is a strong climber, so growing it is not difficult; the challenge is getting it to bloom. Correct pruning is a necessary step to get Wisteria to bloom. To guarantee that wisteria blooms consistently every year, it needs to be pruned twice a year (in the summer and the winter). Flowering depends on pruning. Ladders are required for pruning as the wisteria matures and climbs higher up the wall, increasing the amount of upkeep. Wisteria needs a lot of area because it grows quickly and can be clipped to control its size. Although it may seem obvious, wisteria is best planted in the proper location from the beginning. This is because once established, it is difficult to remove because it has very robust, woody roots.

Wisteria is one of the most beautiful climbing plants, but it’s also one of the most time-consuming and challenging to grow and bring to flower. Your Wisteria will bloom if you follow the Sunday Gardener’s tips and video instructions.