In northwest Ohio, this perennial vine with a lovely scent is in bloom. Wisteria frutescens, an American variety, is less invasive than Chinese varieties (Wisteria sinensis). Butterflies are drawn to blooms because they are a source of nectar. Additionally, skippers, zarucco duskywing, and marine blue use the plant as a host for their larvae. It looks to be tolerant of deer, which is an added benefit for gardeners.
The short, flattened, smooth seed pods (up to 5 long), which ripen in the summer, replace the vine’s blooms. Pods normally split open in the autumn. Deep green compound, odd-pinnate leaves with normally 9–15 lance-shaped leaflets on each leaf.
This vine will thrive in a range of settings, including full sun, part shade, and shade, but favours the former and produces its greatest floral display there. It also favors a slightly acidic soil, and high pH soils have been reported to cause it to turn chlorotic. Once established, it can deal with everything from drought to seasonal flooding.
In Ohio, is wisteria invasive?
It is well known that wisteria take a very long time to bloom. For two to three years after planting, don’t anticipate blossoms. Some readers swear by the following technique to encourage blooming:
- To cut into part of the roots, take a shovel and drive it 8 to 10 inches into the ground approximately a foot and a half away from the main trunk of the wisteria.
- Approximately half of the roots should be damaged for the shrub to be shocked into reproduction (flowering).
- Don’t worry—impossible it’s to harm this unchecked, unwieldy, frequently invasive shrub!
- The flowers of wisteria can also be impacted by chilly winter temperatures.
Native Wisteria
Consider growing a wisteria species that is indigenous to North America if you live there, such as:
- Wisteria frutescens, also known as American wisteria, thrives in zones 5 through 9. Its original states span from Virginia to Texas, the southeast to Florida, and up into New York, Iowa, and Michigan in the north. The vine is 25 to 30 feet long, has glossy, dark-green leaves, and after the plant has begun to leaf out, develops huge, drooping clusters of lilac or purple-blue flowers. Only new wood will display the blossoms. Notably, the blossoms are typically less aromatic than those of Asian wisterias.
- In zones 4 to 9, Kentucky wisteria (Wisteria macrostachya) flourishes. Similar to American wisteria, this late-bloomer is a native of the Southeast of the United States (it is sometimes considered a variety or subspecies of American wisteria). The Kentucky wisteria is the quickest to blossom, bearing faintly fragrant bluish-purple flowers after only two to three years of growth.
- A gorgeous, silvery-blue cultivar of the native Kentucky wisteria called “Blue Moon” is particularly hardy. In late spring or early summer, it blooms. It can go as chilly as -40F. (-40C).
Non-Native Wisteria
- Despite the fact that they are frequently marketed at nurseries and garden centers, Chinese wisteria (Wisteria sinensis) and Japanese wisteria (Wisteria floribunda) are non-native, invasive species, hence we do not suggest them for North American gardens. They can reach lengths of 30 to 60 feet and are hardy in Zones 5 to 9. (and beyond in the Southern U.S.). Japanese wisteria comes in two popular kinds, including:
- Popular plant known as “Honbeni” displays clusters of pink flowers in the late spring.
- “Alba” (also known as “Shiro Noda”) yields beautiful clusters of snow-white flowers in the late spring.
Are Wisteria Toxic to Pets and Humans?
Yes, 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.
If pets or young children frequent the area, it is a good idea to remove the seedpods after the plant has flowered because the material is particularly concentrated in the seeds and seedpods. Unaware children or animals won’t think twice about eating as many seedpods as they can because they are not unpleasant to taste or have an instant effect. In case of ingestion, contact your neighborhood poison control center.
The greatest places for wisteria trees to grow
The greatest way to utilize wisteria’s breathtaking beauty and incredible vitality is to grow it as a little tree, or standard. Long racemes of sweet-smelling May flowers hang down from soft, pruned leaf heads and sway slightly with each breeze. The compact head of a Tree Wisteria looks amazing in a mixed bed of perennials, bulbs, and annuals. The impression is beautiful and dignified.
Please be aware that wisterias typically take a while to emerge from dormancy after planting. Please be aware that your plant won’t start to leaf out until early summer. It will thereafter leaf out at the usual time in succeeding years (midspring).
Choosing a Location: Wisterias grow and flower most effectively in areas with plenty of sunlight, preferably at least 6 hours every day. They do well in any kind of soil as long as it drains well.
In order to plant your bareroot Wisteria, take off the packing and give the roots a few hours in a bucket of water. Then, dig a hole that is both large enough to permit the roots’ spread and deep enough to allow you to set the crown, or the location where the stem and roots converge, 1 inch below the soil’s surface. Insert the roots into the planting hole and arrange them naturally or like the spokes of a wheel. The roots of many woody plants are brittle, so use additional care when positioning them in the planting hole to prevent breaking them. With one hand holding the crown 1 inch below the soil’s surface, use the other to push soil into the hole while circling the roots to prevent air pockets from forming. Then, using both hands, compact the soil close to the crown. To create a basin, create a rim of earth around the perimeter of the planting hole. This basin is used to collect, hold, and direct water to the roots. Finally, thoroughly immerse the plant.
Please be aware that once bareroot plants are taken out of their packing, they dry up rapidly, especially on a sunny, windy day. Until you are ready to plant, we strongly advise that you keep the roots wrapped in wrapping material.
Staking: To keep their heads aloft in severe gusts, tree wisterias need additional support. After planting, drive the wooden stake that came with your tree 6 to 12 inches deep and 1/2 inch away from the plant’s trunk into the earth. Using the plastic tie tape that came with the tree, affix the trunk to the stake numerous times, spacing them apart by about 8 inches. You’ll need to swap out the original stake for a bigger wooden stake or a sturdy steel pipe as the head and trunk grow bigger. Check the tree every spring and autumn to ensure that the stake is securely in place and that the tie tape used to attach the trunk to the stake is not excessively tight and preventing the trunk from expanding. Plants need to be firmly staked at all times.
Watering and Fertilizing: To hasten wisterias’ establishment in the first year after planting, they require the equivalent of 1 inch of water each week. If the sky doesn’t provide enough moisture, water deeply once a week. Plants that are established only require irrigation during extended dry spells. Wisterias don’t need much, if any, fertilizing because too much fertilizer prevents blossom. Give plants a gentle feeding of 5-10-10 or 5-10-5 at a rate of 3/4 cup per square yard in the early spring each year if your soil is particularly weak or sandy.
Overwintering: For the first few winters after planting, cover the main stem with a piece of plastic tubing in cold-winter conditions like ours here in Litchfield (Zone 5 [-20F]). To encircle the stem, make a straight incision from one end to the other and pry the cut open. (Precut tubing could be available at your nearby garden center.) To stop wind and frost from damaging branches on older specimens, cat’s-cradle bind the branches together using twine to form a web of intertwined strings.
Pruning: Tree Wisterias need to have the long, twining branches they generate in the summer pruned lightly but frequently in order to maintain the globe shape of the head. A couple of weeks prior to the first date of your first frost, they also require one severe pruning in late summer or early fall. Remove all branches that are in the wrong place and reduce the current season’s development to just 5 to 6 huge buds (leaving stubs that are about 6 inches long). This drastic haircut inhibits growth and promotes the transformation of some leaf buds into flower buds. Don’t let pruning errors keep you up at night. Wisterias are highly understanding plants; strong growth the following season will give you another chance.
Wisteria trees can endure the winter.
Wisteria (Wisteria spp.) plants have long pendants of fragrant purple or white flowers that dangle in a weeping manner. They are a favorite flower for climbing over arbors, training up a wall, or growing as a conventional tree. When grown, wisteria can readily withstand harsh winters and flourishes in U.S. Department of Agriculture plant hardiness zones 4 through 9. However, young wisteria plants might not be able to withstand the first winter after planting without some protection from frost and chilly winds.
In the fall, water the wisteria plant frequently to maintain moist but not soggy soil. The plants may move nutrients from the soil and store them for the winter by receiving regular watering in the fall. When freezing conditions are predicted, water plants liberally to prevent desiccation of the leaves when the temperatures cause the moisture inside to freeze, leaving frost on the leaves.
To protect the vine’s roots from the cold throughout the winter, cover the base with a 4-inch layer of organic mulch. Anything from crushed bark mulch to dried leaves can be used. To ensure the entire root ball is insulated, keep the mulch a few inches away from the vine and cover a space that is at least 2 feet in diameter.
Wrap the main stem of the wisteria plant with a section of thin-walled plastic tubing. With a razor knife, cut the tubing lengthwise, then pry it open to allow it to fit around the wisteria stem. The plastic tubing is less expensive than using frost cloth or leftover fabric, which are typically far larger than what is required for the stem.
Create a temporary walled enclosure to safeguard the plant. Using a reciprocating saw, extend four 2-by-2-inch wooden posts by about 24 inches beyond the height of the wisteria. Using a hammer, pound the four stakes about 18 inches into the ground. Place the stakes evenly spaced around the plant, 18 inches from the stem.
Frost cloth, burlap, or another type of fabric can be used to cover the stakes. Without letting air escape around the plant’s base, the cloth must be big enough to completely cover the structure. If you require more than one piece of cloth, make sure the ends are at least six inches apart. Set up some bricks or rocks on the ground to hold the extra length in place. The inside temperature of the building stays higher than the outside temperature thanks to the heat that is radiated from the ground surrounding the plant and is trapped by the frost cloth or fabric.
How resilient to cold is wisteria?
Wisteria vines can withstand a wide range of environmental factors, but the majority of types struggle in zones below USDA 4 to 5. Wisteria plants in Zone 3 were a bit of a pipe dream because these beloved plants of temperate climates often died during the cold, prolonged winters. Zones 3 to 9 are favorable for Kentucky wisteria, a chance hybrid that can be found in the swampy regions of south central United States from Louisiana and Texas north to Kentucky, Illinois, Missouri, and Oklahoma. In the cooler location, it even consistently produces flowers.
Japanese and Chinese wisteria are the two varieties grown most frequently. Chinese wisteria is appropriate down to zone 5, whereas Japanese wisteria is a little more hardy and thrives in zone 4. The Kentucky wisteria is descended from the American wisteria, Wisteria frutescens.
The plants naturally grow in highland thickets, riverbanks, and marshy woodlands. While Kentucky wisteria may flourish as low as zone 3, American wisteria is hardy only to zone 5. Wisteria can be grown well in zone 3 thanks to a number of novel cultivars that have been released. Compared to its Asian counterparts, Kentucky wisteria is less pushy and more well-mannered. Even after severe winters, it regularly blooms in the spring with slightly smaller flowers.
In USDA zone 3, Wisteria macrostachya, another plant, has also demonstrated its dependability. It is marketed under the name “Summer Cascade.”
The best wisteria vines for zone 3 are Kentucky wisteria plants. Even a few cultivars are available for selection.
A Minnesotan cultivar named “Blue Moon” sports tiny, fragrant clusters of periwinkle blue flowers. In June, vines can reach lengths of 15 to 25 feet and bear racemes of fragrant, pea-like blooms that are 6 to 12 inches long. These zone 3 wisteria bushes then develop 4–5 inch long, velvety, soft pods. The plant’s delicate, pinnate, dark green leaves on twining stalks only add to its allure.
The aforementioned “Summer Cascade” has racemes of delicate lavender blooms that are 10 to 12 inches long. Other varieties include “Clara Mack,” which has white blooms, and “Aunt Dee,” which has lovely antique lilac flowers.
Which trees are prohibited in Ohio?
You might have seen those trees with the white blooms are now in bloom on your street or at the neighborhood park now that spring has finally arrived in Ohio.
The list of invasive species in the Buckeye State has been updated by the Ohio Department of Natural Resources to include all Callery pear cultivars, including Bradford pears. Anywhere in the state, selling or planting these trees will be prohibited as of 2023.