How deep are wisteria roots?

Planting and cultivation

The Wisteria is one of the most rustic, climbing plants ever known to our climate, making it easy to coltivate. However when the plant is young it needs to be looked after like every other plant.
Soil: Where should it be planted? Of course the most fresh and fertile soil is ideal but the Wisteria is very adaptable therefore able to thrive well even in dry and stony soils, but not in calcareous or limestone ones. (see disorder – chlorosis)
Planting: Nowadays, we can easily find on the market pot grown Wisterias which can be planted in any season, however in colder climates, planting is usually advised in spring – Dig a hole in the ground, around 50cm wide and 40cm deep, then mix in the hole well rotten manure and 200-300g of artificial fertiliser, the best are slow released ones. Make sure the plant pot and the planting ground are well watered and maintained as such after planting until the rots are grown and the plant is established. Particular attention goes to the plant pot; often the nursery potting compost is quite dry and if the plant pot is not well watered before planting it will be difficult for the roots to absorb water even if the surrounding ground is wet.
Fertilising: Continue to apply a balance fertilizer (nitrogen, phosphorus and potassium) once or twice a year until the plant is well established . Then gradually reduce the quantity of nitrogen until finally eliminate it. Healthy adult plants should only be given a phosphorous based fertiliser once a year.
Climate and position: The wisteria prefers sun but it will grow in shady positions too where it will flower later and less abundantly. The wisteria thrives well all around Italy, up to 1000m altitude.
Training and support: Being a climbing plant the wisteria should be guided in a way which allows it to attach and eventually wrap and wind itself around the chosen support. Begin to shape the plant in the direction and form desired from the first year. Don’t let the main stems winding into a metal frame, they grow so rapidly and strongly that they could bend the structure: in such a case the plant should be left to grow straight attaching it (not too tightly) with plastic string or straps to the frame.
The roots: The wisteria roots spread so strongly and abundantly that if planted near walls or pavements they can easily grow into them causing serious damage . To prevent this from happening it is advised, whilst planting, to insert a corrugated plastic panel which will force the roots to take other directions, as they are unable to pass through it. Place the plastic panel (at least 2m long) 80cm deep, between the plant and the wall or pavement (or the surface to be protected). In the case of walls and pavements made with cement this problem does not exist.
How to choose the correct variety? – Have a clear picture in your mind about the look you would like to achieve for your landscape. The first point to bring in to consideration should be the flowering time and the number of flower buds. Think about the atmosphere that you want to create and how different colours (blue, white or pink) could affect that at that particular time of year. Keep in mind also the spectacular impact that even the slightest difference in tone can create. In conclusion remember that the wisteria is an overwhelming, vigorous, centenary plant which will become a very evident and eye-catching part of the landscape which you are creating.
Purchasing a wisteria – The wisteria grows very quickly in its first few years as a result of this it is not necessary to buy a very large plant, unless the desired effect and shape of a particular plant is needed right away. Many experts advise purchasing the wisteria in spring after blossoming. This is excellent advice, however it does limit the purchaser in buying and planting the plant in April/May and exempt the beautiful Japanese variety (Wisteria floribunda) which have a juvenile period of 2 to 4years in which they don’t bare flowers.
The plant should be always sold with a descriptive label attached, which you can trust. This label usually has a photograph of the plant, the botanical name and it should also include the common name where it exists. The label should have some descriptive and concise information about the up keeping of the plant and it should also act as a sufficient assurance and correspondence to other varieties.
See one of our typical labels for the wisteria.

Growing Wisteria

Few plants can rival the dramatic spring beauty of a wisteria vine in full bloom. Despite the showy flowers and delightful scent, wisteria plants have acquired a reputation for being difficult to grow. Don’t be fooled. With the right growing conditions and some occasional pruning, wisteria is a beautiful, fast growing vine – and a worthwhile addition to nearly any garden.


Plant Characteristics

Popular for their long, hanging clusters of violet flowers, there are around a dozen wisteria species available to gardeners, including two native to North America. The most common types grown are the Asian species Japanese wisteria (W. floribunda), and Chinese wisteria (W. sinensis).

Japanese wisteria tends to have more vibrant color blooms and Chinese wisteria a sweeter scent. Both species need a large amount of growing space and look very similar in appearance. You can tell the difference between the two by the way they climb. The stems of Japanese wisteria twine around supports in a clockwise direction, while the stems of Chinese wisteria twine in a counterclockwise direction.

The Best Zones for Wisteria

Wisteria grows best in zones 3 to 9. Not all varieties are suited to all zones, however, so check carefully to make sure the wisteria you choose is a proven performer where you live. If you lack space (or the ability to erect a sturdy support structure), the smaller American forms of the vine, such as Kentucky wisteria (W. macrostachya) or American wisteria (W. frutescens) don’t grow as quickly and can be good substitutes for smaller gardens.


Where to Grow Wisteria

Wisteria will grow in partial shade and marginal soils but performs best in sunny locations (6 or more hours per day) and in moist, fertile soils that drain well. Wisteria needs a large amount of growing space. These plants are vigorous climbers (growing 10 feet or more annually) and are easily capable of climbing to heights of 25 feet.

Once established, the Asian species can become invasive and difficult to get rid of – especially in the east. To help restrain the plant’s spreading root system, wisteria can be planted in large containers buried in the ground.

Planting Wisteria

  1. To plant wisteria, work the soil deeply (18 to 24 inches) around the hole where the vine will be planted.
  2. Mix a couple handfuls of compost or well-rotted manure in with the original soil. Advertisement
  3. Set the plant on the ground at the same height it was growing in the pot.
  4. Water in well and add a layer of organic mulch around the base of the plant.
  5. Keep your newly planted wisteria watered well for several weeks after planting to allow it to become established.

Pruning Wisteria

Wisteria needs to be pruned a minimum of twice yearly to keep plants tidy and promote flowering.

  • 1st-Summer Pruning (just after flowering): Cut off the tips of all of the side shoots as well as the tips of any new growth. Also, remove any suckers that appear at the base of the plant.
  • 2nd-Late Winter Pruning: Cut the main stems back by about half. You may also shorten side shoots slightly; cut them back to only a couple of inches from where you see the flowering spurs (little pegs).


Training Wisteria

You never have to worry about over-building supports for wisteria. Mature vines are heavy and will require ample support. To train young plants to grow on a trellis or arbor, choose an upright stem to serve as the leader and secure this to the support. You can then remove some of the side shoots and train the remaining shoots to grow horizontally across the supports, or simply let them all twine across the supports naturally. Pinch off the main leader when it reaches the desired height.

Five Reasons Wisteria Fail to Bloom

One of the more frustrating aspects of growing wisteria is waiting for them to reach maturity and then watching them fail to bloom. Here are five common reasons wisteria fail to produce flowers:

  1. Immature plants. Depending on whether you are starting new plants from seeds, cuttings, or young nursery stock, it can take 5, 10, or even 15 years or more before wisteria start to produce flowers. Start with grafted plants or those grown from cuttings that are known to have flowered relatively young. These plants usually flower much sooner than those grown from seed.
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  3. Too much nitrogen (or insufficient phosphorus). Some gardeners make the mistake of over-fertilizing wisteria to encourage them to flower. This can actually work against them, because excess nitrogen encourages the plant to produce foliage, usually at the expense of flowers.
  4. Planting too deeply. Setting plants in the ground too deeply may result in a delay of flowering or prevent them from blooming altogether.
  5. A lack of sun. Too much shade can cause vines to flower poorly. Although some types of wisteria may be root-hardy to Zone 4, many varieties won’t bloom reliably there. In Zone 5, plants may sometimes fail to bloom after a severe winter freeze kills off flower buds.
  6. You’re being too kind. Pruning is key to getting wisteria to flower. You have to keep pruning all of those errant new vines that keep sprouting up. Depending on the soil the species you’re growing, and environmental conditions, you may need to snip shoots as often as every 4 to 6 weeks.


Growing Wisteria from Seed

Wisteria plants are often started from layered cuttings, but they are also easy to grow from seed.

  1. When the seedpods turn brown in the fall, remove the seeds and allow them to dry.
  2. Store them in the refrigerator until spring.
  3. In the spring, sow seeds directly in the ground (or in containers) after soaking them in water for 24 hours.
  4. It’s important to note that wisteria grown from seed may not resemble the parent plant in form or color.
  5. They will also take longer to reach flowering size – anywhere from 10 to 15 years.

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Wednesday – May 05, 2010

From: Westminster, MD
Region: Mid-Atlantic
Topic: Septic Systems
Title: Should non-native invasive Wisteria be planted near well and septic system?
Answered by: Barbara Medford


I was told not to plant my Wisteria vine near my septic or well because the root will get into it and cause me many problems. Is this true?


We are really hoping you are not using the past tense, as in “I already planted it there, now what do I do?” And we are assuming you are talkng about the non-native plant, either Wisteria sinensis (Chinese Wisteria) or Wisteria Floribunda (Japanese Wisteria). Wisteria frutescens (American wisteria) is a native version, not quite as aggressive as the non-natives, but still a woody plant. It is native to Maryland; Carroll Co. is in USDA Hardiness Zones 6a to 7a and American Wisteria is hardy in Zones 6 to 9. From this Ohio State University website Growing Wisteria, we extracted this information to indicate which plant you probably have in your garden:

“Two species of wisteria are typically grown in home gardens: Wisteria sinensis or Chinese wisteria, and Wisteria floribunda or Japanese wisteria.”

The first problem for us is that the Lady Bird Johnson Wildflower Center is committed to the use, protection and propagation of plants native not only to North America but to the area in which they are being grown. The second problem, and this has to do with your septic lines and well, is that they are vigorously growing, woody plants. You don’t want any woody plants close to your lateral lines, as in trees and shrubs. They are the ones that send roots out far beyond their driplines, sneaking up on you. But you don’t want to leave that area completely bare, because you know it wouldn’t stay bare, it would get weedy and unless it was mowed, some of those “weeds” would grow up to be woody plants. We don’t know how your lateral lines or well are situated, but you do need to be aware of them when planting in that area. As large and aggressive as wisterias are above the ground, you can bet their roots are equally or even more so.

If you haven’t already planted anything there, our recommendation is to not use woody plants, but native grasses, even wildflowers. The long fibrous roots of grasses and herbaceous flowering plants will help hold the soil, but will not interfere with the underground construction. If you have already planted the wisteria, our recommendation is: LOOK OUT!

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Mistakes to Avoid when Growing a Wisteria

Wisteria is among the most spectacular vines in any home garden. But growing it can often be very challenging. If you’re thinking about growing wisteria in your garden, consider the following obstacles.

Dry soil

Although wisteria is remarkably adaptable, it does best in a fertile, moist soil environment. When planted in a dry soil or soil that isn’t kept sufficiently moist, the vine can go into shock and die. Lack of watering is one of the most common mistakes gardeners make with wisteria.

Too Much Fertilizer

Another frequent mistake is to to overfeed the wisteria. Once the vine is established, wisteria doesn’t need much in the way of fertilizer. Instead, give the vine a shovelful of compost in early spring. This gives it sufficient nutrients for the season.

Insufficient Support

Wisteria is a climbing vine that requires sturdy support. Home gardeners frequently underestimate the weight of a mature wisteria and use supports that cannot sustain the plant. Over time, lack of proper support will cause the wisteria to collapse and grow over anything in its path. Remember, these vines can reach 25 feet in height.


When wisteria is neglected and not pruned sufficiently, the result is often a massive, woody tangle of vines. Gardening experts recommend pruning off a good 90 percent of new growth each year as a rule of thumb. This isn’t as outrageous as it sounds when you consider that a single runner can grow up to 12 feet in a year.


Home gardeners often see a sturdy wisteria that’s taken over and think there’s no such thing as overpruning. But when you remove too many of the flowering short laterals, which originate from the main trunk or stem, it will cause a shortage of blooms or a sparse-looking wisteria the following spring. The main idea is to remove or trim the long, wild runners and leave the short laterals to flower at will.

Unnecessary Removal

This often occurs when a wisteria has been seriously neglected for years, allowed to grow with abandon until it completely covers the side of a house, wall, porch or other structure. The runners get into eaves, heave foundations, crack concrete and generally cause a lot of damage. Avoid the temptation to completely remove the wisteria. That’s not only unnecessary, but it will rob the home garden of a wonderful plant specimen.

The solution is to do a thorough pruning job, cutting well below where you want the wisteria to re-grow. The new growth will occur the following spring. When rehabilitating an overgrown wisteria, remember that the plant will be only bloom for a few years, but will eventually flower again. Some major stems will partially or totally die. Cut off any dead parts as time goes on.

Tools And Timing

Two other mistakes common when growing wisteria are use of the wrong tools and underestimating how long wisteria takes to bloom. For pruning vines and water spouts, use long-reach pruners (not pole pruners). For trunks and woodier branches, use loppers, hand pruners and a pruning saw. Make sure all your tools are clean and sharp.

In terms of timing, expect to wait 5 to 6 years for Chinese wisteria to bloom, and 10 to 15 years for other varieties and cultivars.

Wisteria Root System Information – How Big Do Wisteria Roots Grow

Wisteria are strong vines that climb aggressively. The root system of a wisteria is equally aggressive beneath the soil. Whether you choose Chinese wisteria (Wisteria sinensis) or Japanese wisteria (Wisteria floribunda), plant them far from your pipes and sewer system. How big do wisteria roots grow? Are wisteria roots aggressive? Read on for answers to these common questions about wisteria root systems.

How Big Do Wisteria Roots Grow?

When you consider how tall wisteria vines can grow, it just makes sense that the wisteria root system is strong and aggressive. For example, Chinese wisteria can shoot up 60 feet with stems up to 15 feet in diameter. Both Chinese wisteria and Japanese wisteria are the two most popular types of garden wisteria in the U.S., and both grow and spread aggressively.

The wisteria native to the United States is Wisteria frutescens. It grows to 30 feet tall and the roots are a bit less aggressive than the imports. As a woody plant, however, it still has powerful roots that you don’t want close to your sewer pipes.

Are Wisteria Roots Aggressive?

A wisteria root system digs deep and spreads wide in order to anchor the huge vine. Are wisteria roots aggressive? Yes, the root system of a wisteria is very aggressive. Since the wisteria root system is so large and powerful, you should avoid planting wisteria near walls or pathways. The root system of a wisteria can easily damage these.

Experts recommend that if you locate a wisteria near a structure or walkway, you should insert a corrugated panel some 6 feet long and several feet wide beside the plant to divert the roots.

Wisteria Root Removal

You may be thrilled at how fast your new wisteria grows, throwing up a vigorous vine and developing a powerful wisteria root system. But if one day you decide to remove the vine, you will be less thrilled.

Wisteria root removal can be a big headache. You can perform this manually, mechanically or with chemicals. However, you will probably have to invest quite a lot of time before you are certain the wisteria root system is completely eliminated.

When the wisteria you want to remove climbs up walls or trees, you’ll do best to cut the trunks. After that, apply herbicide to the cut surfaces. If you want to remove a thicket of wisteria, try applying a foliar herbicide. Other methods applied to a group of wisteria will disturb the soil too much.

Blue Chinese Wisteria Tree

If you are searching for an absolutely stunning focal point in your landscape, you need to look at this best-selling tree form Chinese Blue Wisteria (Wisteria sinensis).

Usually, Wisteria is a fast-growing vine. You may have seen this vine artistically draped over sturdy structures adorning castles in Europe, wineries in Napa Valley, or those huge estates featured on Lifestyles of the Rich & Famous.

But, here’s a secret we’ve shared with so many happy customers….

You can also enjoy the amazing, fragrant flowers of Wisteria on a cute, little accent tree. We’ve trained this amazing plant into a knock-out, single stem tree with a nice, sturdy trunk. Our expert growers work diligently to create a one-of-a-kind, original masterpiece for you.

We have an excellent strain we’ve been growing for years. Our Blue Chinese Wisteria blooms feature a dark purple bud that opens to a lovely icy lavender and purple flowers, and fades to blue as the flowers age. As the flowering season progresses, the oldest blooms fade to that magnificent blue that people just love.

WOW! It makes a one-of-a-kind impact in your landscape. Use one or more as a perfect touch for your front yard, or near your patio.

In late spring and early summer – before the leaves appear – the tree explodes in long streams of sweet-smelling flowers that can range from sky blue to rich lavender. The elongated flower panicles can reach up to a foot in length.

The flowers simply drip from the tree in a lavish display. And, because the flowers appear before the leaves emerge, the show is even more dramatic.

This is not a tree you’ll be able to ignore in full bloom. You’ll love the fabulous range of these cool tones featured in your yard.

What about the delicious fragrance? Everyone in the neighborhood will appreciate the sweetly scented flower clusters.

You can rest assured that this is the ORIGINAL Blue Chinese Wisteria Tree. These are amazing tree forms of the popular Wisteria vines that grow almost anywhere in the country.

We also think you’ll appreciate their small, dark green leaves that turn a lovely golden fall color for interest all through the season. The Blue Chinese Wisteria tree is easy to grow, it grows quickly, and is widely adaptable all across the country.

People come back to us to place additional orders of this incredibly popular tree. They can’t get enough, and we bet you’ll feel the same. Order yours today!

How to Use Blue Chinese Wisteria in the Landscape

Maybe you’ve seen these beautiful trees in person, or online, and just have to have one (or more!) for yourself. People all across the country are growing this tree-form Wisteria as a very special specimen plant.

Use them as a highlight in your courtyard area. Do you have a big raised berm in your front yard? This is the perfect tree to use to set off your berm planting. If you really want something that stands out, try two Blue Chinese Wisteria trees on either side of your front entrance. Instant curb appeal!

Of course, you’ll want to see and smell the flowers in early spring. Use them near your patio for a delightful yearly treat.

They’ll even work well in large containers. Need a pretty privacy screen? Use these special plants in large containers placed strategically to block your view. What a visual treat!

A classic formal use for tightly pruned Blue Chinese Wisteria is to place 4 of them in a rectangular bed that will be viewed from all sides. Evenly space the trees to give them room to reach their full size, then underplant with your favorite spring flowering bulbs.

Next, follow with perennial groundcover or bright annuals. Be sure to frame the edge of your formal bed with a short, sheared Boxwood or Holly hedge to give it a formal outline separating it from the grass. This is a fantastic look to showcase these small trees!

Of course, if you have the room, you can grow it as a casual tree out in the yard. In this application, you might want to let it grow a bit wider and taller.

Can you see how many ways you can use this beautiful tree? The secret to success is all in the pruning. Read on to see how you can easily shape your new trees to best suit your style.

#ProPlantTips for Care

Please take special note of these tips so you get the very best results.

Tree form Blue Chinese Wisteria are fast growing, disease resistant, and are highly drought tolerant once they are established in your yard. Please choose your planting site carefully.

Place them where they’ll be noticed. After all, you’ll want to reap the glory each spring, and secure your neighborhood reputation as a fantastic gardener with a green thumb.

Go ahead, take all the credit! Be ready for the questions and the praise.

They’ll produce the most abundant flowers if you plant them in a spot that gets full sun all day long. If they do get some light shade, they can still thrive for you. The sunnier, the better!

Blue Chinese Wisteria tree form will adapt to just about any kind of soil, but it must be well drained. Check to see if your ground holds puddles after a rain. If so, mound up top soil 18 inches high. You can then dig a hole plant your tree in that mounded up soil for better drainage.

Give your tree plenty of room to grow. If you choose to grow them in a container, just make sure to use a large container with plenty of drainage holes.

Please do baby them a bit when you first get them planted. Water regularly to get your new tree established. After that, it will be drought tolerant.

Also, for the first year or two, you’ll want to use a sturdy stake to help it stand up straight. You can imagine how heavy those flowers are! A little support is very appreciated. You’ll leave that stake until the main trunk is wide enough to support the whole plant all by itself.

Just add our Arbor Springs kit to your cart and keep it easy for yourself.

Be careful not to use lawn fertilizer near your tree, as too much nitrogen will feed the leaves, not the flowers. Doing so will delay the beautiful blooms.

Blue Chinese Wisteria is a plant that deer seem to leave alone. Keep in mind that deer may sample any plant if food is scarce.

Blue Chinese Wisteria Tree Pruning

Decide on the mature look you want while your tree is young. Short and wide? Oval? Asymmetrical?

You can think of it as deciding on your tree’s “hairstyle”. Decide how long you want the branches to grow and the style that suits your tree best in your yard. Then, just give it regular trims to keep things nice, tidy and flowering beautifully.

You have a lot of influence on how your plant looks once it’s mature just by pruning the tree for shape when it’s young.

Pruning is the very best method to help your tree produce flowers, too. The goal is to have plenty of nice, short flowering stems for plenty of spring blooms within the crown of your tree.

The branches will work as a framework to support the spectacular, heavy flowers. Decide which structural branches you’ll keep and allow them to grow out and thicken up each season.

In late summer, you’ll shape your tree for size and to reinforce that structure.

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