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.
Other problems
A mature, seemingly robust wisteria will occasionally pass away and be replaced by a new, healthy branch emerging from the ground. Failure of the wisteria graft may be the reason of this.
Wisteria is sensitive to both of the fungi that cause phytophthora root rot and honey fungus, which are less frequent causes of failure.
Unusual brown blotches and marks on the leaves, typically with a yellow edge, may be a sign that a fungus has infected them. Viruses can also harm wisteria and powdery mildew.
Infestations of scale and, less frequently, wisteria scale can affect wisterias.
While we hope this information may be useful to you, we always advise reading the labels on your plants that provide care instructions.
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.
The ideal places for wisteria to grow.
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.
When should wisteria be done?
If wisteria seedlings have at least two sets of leaves or are 4 to 5 inches (10-13 cm) tall, experts advise planting them outside in the spring or summer. Additionally, you must make sure there are 45 days before the first anticipated frost in your area before planting.
Your seedlings should be planted in a spot that receives full sun for at least six hours each day. You should put your seedlings close to a wall, trellis, or fence and make sure the soil is well-draining.
Give your wisteria plant enough space to spread out and climb since it is a fast-growing vine that can grow 10 feet (3 meters) or more in a year.
Again, cuttings will result in blooming wisteria plants much more quickly, and the new plants will reproduce the qualities of the parent plant if you’re not willing to wait up to fifteen or more years for blossoms.
The wisteria’s rate of growth
Nothing compares to the splendor of a wisteria arbor in full bloom, but sadly, many Midwestern gardeners are unable to grow these exquisite vines.
Japanese wisteria (Wisteria floribunda) and Chinese wisteria are the two varieties of wisteria that are most frequently planted in our region ( Wisteria sinensis).
Japanese wisteria is famous for its fragrant violet blooms, which are produced in clusters that range in length from 8 to 20 inches. A cluster’s individual blooms open one at a time, starting at the base.
Chinese wisteria often has clusters that are less than 12 inches long, with slightly larger individual blooms. A cluster of flowers also has a tendency to open at the same time. Chinese wisteria is less fragrant and less resilient than Japanese wisteria. Both species have cultivars that feature white blooms.
Wisteria is an aggressive twining vine that can become highly invasive in some places. Strong support is necessary for the vines to maintain their rapid growth. When wisteria is established in the right setting, it can grow up to 10 feet each year. It functions best in neutral to slightly alkaline, deep, moist, but well-drained soils.
Since the majority of gardeners are attracted to this plant for its flowers, they are very irritated by its infamous propensity to just grow greenery. This irritating issue may be caused by a variety of factors, including the plant’s immaturity, an excess of nitrogen, a deficiency in phosphorus, poor-quality plants, and an excessive amount of shadow.
Before they can start to produce flowers, Asian wisterias need to attain a certain level of maturity. In actuality, it may take the vines up to 15 years or more to bloom.
Those who have had success with wisteria frequently advise root trimming, using superphosphate, severe shoot clipping, and planting in full light. Most importantly, you should begin with high-quality plants that were grown from cuttings of plants that are known to bloom when they are still quite young. Take cuttings of the stem tips in July if you know someone who is prepared to part with a beautiful specimen. Avoid planting seedling vines since it is impossible to predict their flowering habits due to the genetic diversity of seed reproduction.
Wait until late spring or early summer to prune these vines since they develop their blossoms on last year’s wood in mid- to late May. To keep the plant manageable and regenerative, severe pruning back to three or four buds is frequently advised.
A few native species of wisteria are a little more “tame” than their Asian counterparts. These indigenous species attain flowering age earlier than Asian species because they bloom on the growth of the current season. Although they bloom slightly later in the spring, they can rebloom throughout the summer.
The 20–30 foot tall American wisteria (W. frutescens) blooms its flowers in 4-6 inch long, compact clusters. The most popular cultivar, “Amethyst Falls,” has fragrant lavender-blue blooms. Although ‘Nivea’ has longer clusters of white blossoms, it is less aromatic.
Wisteria macrostachys, which grows in Kentucky, produces flower clusters that are 8 to 12 inches long and densely covered with blossoms. Some people believe this to be an American wisteria subspecies. The hardy Minnesota cultivar “Blue Moon” has incredibly fragrant blossoms that start to develop in June and continue throughout the summer. Both ‘Aunt Dee’ and ‘Clara Mack’ have blooms that are a light lavender color.
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.
