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.
Wisteria has an impact on foundations?
On a south-facing wall of our home, a Chinese wisteria (Wisteria sinensis) is growing. There are a lot of flowers there, but I worry that the roots may spread beneath the land and end up harming the house. Should I trim it?
Only areas with soil will support wisteria growth. Therefore, it won’t wander under the home.
Oh my goodness, no! Only areas with soil will support wisteria (below). Therefore, it won’t venture under the home, not least because the footings of the structure act as a sturdy obstruction. Every spring, keep the plant well-mulched with manure or compost. Every summer, soon after flowering, cut back the new growth to 6 inches of a healthy bud. Then, just sit back and enjoy it.
Can I do the same with my vegetables since I like to save and plant flower seed?
You can, indeed. If allowed to flower, all vegetables will generate seed, and the majority of those seeds can be saved and used the following year. Some, like peas and beans, are simpler to grow than others, but you should attempt to leave a few plants from each crop to flower and set seed. Then, gather the mature seed heads, allow them to fully dry, and store them in a paper envelope in a cool, dry location.
Can wisteria be grown close to a house?
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.
How can you defend wisteria from the house?
I usually move quickly past my wisteria with little fear, and occasionally when I speak to it, I tell it, “You are a plant. The human is me. I am in command. But until I came out with a flawless method to control it, neither the wisteria nor I really believed it to be the case.
Not getting wisteria to grow is the difficult part
It enjoys poor soil, direct sunlight, and the side of your house, but there are ways to teach it to grow well next to the house. Wisteria needs the assistance of a sturdy trellis system for that.
Wisteria tendrils will wrap themselves around any available supports in either a clockwise or counterclockwise direction. I used substantial stainless steel components to build a grid system at my home so that the wisteria could thrive.
The grid’s components include affordable hardware purchases (you can also buy them online from Sears). I spent $1.99 per 3.75-inch-long stainless steel Lag Eye Bolt (Top), $62 for a 125-foot spool of stainless steel cable, and $24.05 for a box of ten stainless steel turnbuckles.
Once your trellis is set up, you may train it to grow next to the grid by tying individual branches to the cable. Pruning wisteria ferociously will keep it in check. Trim side shoots along major branches to a length of 3 inches in the fall and winter.
How close to a wall should wisteria be planted?
on a wall. Wisteria should be trained as an espalier with horizontal support wires (3mm galvanized steel) spaced 30 cm (1 ft) apart for the best results when grown against a wall. Plants will develop a robust spur system with time and twice-yearly trimming.
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).