Growing Wisteria

How to Plant, Grow, and Care for Wisteria

Wisteria
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A high-climbing vine, wisteria blooms vigorously in spring with large, drooping clusters of lilac or bluish-purple flowers. Here’s how to plant, grow, and care for wisteria in your garden!

About Wisteria

Wisteria is a vining plant with cascades of blue to purple flowers that look spectacular hanging from a pergola or archway in spring and early summer. However, this vine is a fast and aggressive grower—often reaching 25 to 30 feet long—and is known to grow quite heavy. Wisteria vines will work their way into any crook or cranny they can reach, so it’s advised to not plant them too near to your home.

Wisteria flowers are beautifully fragrant, providing a feast for the senses. After flowering, a brown, bean-like pod stays on the plant until winter. Blooms only appear on new wood.

Is Wisteria an Invasive Plant?

Chinese wisteria (Wisteria sinensis) and Japanese wisteria (Wisteria floribunda) are not native to North America and are considered invasive species in some states. The native wisteria species, American wisteria (Wisteria frutescens) and Kentucky wisteria (Wisteria macrostachya), are great alternatives to the Asian species, so if you’re planning on adding a new wisteria to your garden, we suggest that you go with one of the North American species.

Wondering how to tell the difference between the Asian and North American species?
Asian wisteria are aggressive growers with fuzzy seed pods, while North American wisteria are not quite as aggressive in their growing habits and have smooth seed pods and fruits, as well as more-or-less cylindrical, bean-shaped seeds. Another difference is that American and Kentucky wisteria’s flowers appear after the plant has leafed out in the late spring, whereas the Asian species’ blooms appear before their foliage.

Planting

How to Plant Wisteria

  • Plant wisteria in fertile, moist, but well-drained soil. 
  • Plant in full sun. Though wisteria will grow in partial shade, it probably won’t flower. Sun is essential.
  • If your soil is in poor condition, add compost; otherwise, wisteria will grow in most soils. Learn more about soil amendments and preparing soil for planting.
  • Plant in the spring or fall.
  • Dig a hole as deep as the root ball and 2 to 3 times as wide. Space plants 10 to 15 feet apart.

Where to Plant Wisteria

  • Choose a site that will not overwhelm nearby plants, as wisteria grows quickly and can easily overtake its neighbors.
  • Wisteria is also known for growing onto (and into) nearby structures, such as houses, garages, sheds, and so on. We strongly recommend not planting wisteria too close to your home!
  • Wisteria vines require a very sturdy structure to climb on, such as a trellis or pergola. Mature plants have been known to get so heavy that they break their supports, so plan with care and build your structure with hefty materials.

Wisteria on brick house
Wisteria looks lovely climbing up the side of a home, but plant with caution; wisteria vines are very powerful and will find their way into any crack or crevice!

Care

Caring for Wisteria

  • Each spring, apply a layer of compost under the plant and a 2-inch layer of mulch to retain moisture and control weeds.
  • Some gardeners swear by phosphorus to aid with flowering. Scratch a couple of cups of bone meal into the soil in the spring and then add some rock phosphate in the fall.
  • Water your plants if you receive less than one inch of rain each week. (To know how much rain you are getting, you can place an empty tuna can outside and measure the depth of water with a measuring stick.)

Pruning Wisteria

  • Pruning is the secret to good flowering, as wisteria only blooms on new wood.
  • Prune wisteria in late winter. Remove at least half of the prior year’s growth, leaving just a few buds per stem.
  • If you want a more formal appearance, prune again during summer, after traditional flowering.
  • For more blooms, try cutting back the rampant shoots every two weeks during the summer.
  • Do you have a new wisteria? Cut the vine back severely right after planting. Then, the next year, cut the main stem or stems back to 3 feet of the previous season’s growth. Once the framework is full size, shorten further extension growth in midsummer to where growth began for that season.
  • Informally grown, mature plants need little or no subsequent pruning.
  • For a formally trained plant, cut side shoots back to 6 inches in summer, then shorten them again in winter to 3 buds.
  • Wisteria will resprout with vigor if cut back severely, but this pruning should be avoided, if possible, because new shoots may take some years before they flower.
  • Get more tips for pruning wisteria.

Wisteria on pergola

When Your Wisteria Won’t Bloom

Wisteria are notorious for taking a long time to bloom. Some readers have sworn by this method to spur on blooming:

  • Take a shovel and drive it 8 to 10 inches into the ground about a foot and a half away from the wisteria’s main trunk to slice into some of the roots.
  • Damage about half of the roots and the bush will be shocked into reproduction (flowering).
  • Don’t worry—it’s difficult to hurt this rampantly-growing, unrestrained, often-invasive plant!

Pests/Diseases

Recommended Varieties

Wit & Wisdom

Are Wisteria Toxic to Pets and Humans?

Yes, all parts of the wisteria plant contain substances called lectin and wisterin, which are toxic to pets, livestock, and humans. These toxins can cause anything from nausea and diarrhea to death if consumed in large amounts.

The substance is especially concentrated in the plant’s seeds and seedpods, so removing the seedpods after the plant has flowered is a good idea if pets or children are often nearby. The seedpods do not have a foul flavor or an immediate effect, so an unknowing child or pet won’t hesitate to eat as much as possible! Call your local poison control center in case of ingestion.

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Growing Wisteria

Botanical Name

Wisteria

Plant Type Shrub
Sun Exposure Full Sun, Part Sun
Soil Type Any
Soil pH Varies
Bloom Time Spring
Flower Color Blue, Purple, White
Hardiness Zones 4, 5, 6, 7, 8, 9
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