28 Invasive Plants to Avoid in the Northeast
Do you live in the northeastern United States and want to avoid invasive plants in your landscape? It doesn’t take long for invasive plants to take over your garden and spread into nearby natural areas. In this article, gardening expert Liessa Bowen introduces 28 invasive plants you should avoid with suggestions for better alternatives.
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Invasive plants are easy to grow and hard to get rid of. Once established in an area, they spread rapidly, often crowding out more desirable species and making it difficult to manage a garden. These plants originate in other regions of the country or from other countries entirely. Here, I’ll share common invasive plants to avoid in the Northeast.
Not all non-native plants are invasive, however. Some grow perfectly well in a landscape setting and never get out of control. Those that become pesky invaders proliferate, thrive in varied conditions, and spread easily and aggressively, harming other plants and taking over habitat for native species.
You don’t have to let invasive plants take over your garden. Learn to identify which species are most common in your region. Don’t plant them, and try to remove those already in your yard.
The following is a list of 28 invasive plants you might encounter in the Northeastern United States, plus better-behaved garden plants you can grow instead!
Amur Honeysuckle
The Amur honeysuckle and other varieties of bush honeysuckle (Lonicera spp.) are native to Europe and Asia. Originally landscaping plants, they escaped cultivation and are now widespread.
These medium-sized shrubs invade fields, forests, and disturbed areas. They are fast-growing and spread by vigorous root suckers and seeds, creating dense colonies and outcompeting native vegetation.
Alternative: Fragrant sumac (Rhus aromatica) is a small native shrub. It develops stunningly colorful fall foliage, and birds love the fruits.
Autumn Olive
Autumn olive (Elaeagnus umbellata) is a deciduous shrub from Asia. Because of its ability to grow in varied habitats and colonize quickly, gardeners use it as erosion control.
This plant has become invasive in fallow fields, woodland edges, roadsides, and disturbed areas. It outcompetes native plants and is very difficult to control. Autumn olive has white spring-blooming flowers. By mid-season, it produces an abundance of small fruits eaten by birds and other wildlife, further allowing autumn olive to spread.
Alternative: Green hawthorn (Crataegus viridis) is a small tree native to the eastern United States. It produces showy white flowers in the spring that attract butterflies and beautiful red berries in the fall that attract birds.
Bighead Knapweed
Bighead knapweed (Centaurea macrocephala) is native to Iran, Turkey, and the Caucasus. This large perennial flowering plant has showy, yellow, thistle-like flowers and prickly leaves with sharp edges. It produces copious numbers of seeds distributed by wind and passing animals.
These plants are not picky about growing conditions and can form dense, impenetrable thickets in pastures, fields, and other disturbed, sunny areas.
Alternative: Rough blazing star (Liatris aspera) is a native wildflower that blooms from late summer into fall. The fluffy, purplish flowers attract many insect pollinators and hummingbirds.
Black Swallowwort
Black swallowwort (Vincetoxicum nigrum) is a deciduous vine originating in Europe. It is the close relative of the pale swallowwort (Vincetoxicum rossicum), which is also invasive.
Swallowworts are vigorous vines that invade fields, forest edges, and roadsides, blocking out native vegetation. These plants bloom in the summer and produce pods of windblown seeds, helping them disperse and colonize new areas quickly and efficiently.
Alternative: Black swallowwort bears some resemblance to the native milkweeds (Asclepias spp.), any of which would be a better alternative. Milkweeds have beautiful flowers, attract many pollinators, and are the larval host plant for the monarch butterfly caterpillar.
Callery Pear
The Callery pear (Pyrus calleryana), also commonly known as the Bradford pear, is an invasive plant prevalent in the Northeast that originated in Asia. You’ll see it as a landscaping plant, particularly along roadways and in new housing developments, because it grows fast and tolerates a wide range of conditions.
Callery pear blooms in the springtime with dense masses of unpleasant-smelling white flowers. These plants have escaped cultivation and have naturalized in many states, disturbing natural communities and displacing native tree species.
Alternative: The redbud crabapple (Malus x zumi var. calocarpa) is a showy tree native to Japan. It produces fragrant white flowers in the spring, which attract pollinators, followed by small red fruits in the summer, which attract fruit-eating birds.
Common Reed
Common reed (Phragmites australis) is a tall perennial grass native to Europe and Asia. This grass can grow 14 feet tall and create dense, impenetrable stands, particularly in wetlands.
As the invasive reed plant invades wetlands, it chokes out Northeast native vegetation, reducing biodiversity and significantly altering the natural habitat of mashes, shallow lakes, shorelines, and other wetland areas. It spreads quickly by self-seeding and aggressive rhizome growth.
Alternative: Tufted hair grass (Deschampsia cespitosa) may not grow as tall as the common reed grass, but it is much easier on the environment. This clump-forming grass is a nice addition to a rock or prairie garden.
Cow Parsley
Wild chervil (Anthriscus sylvestris), also known as cow parsley, is a biennial herb that originated in Europe and western Asia. It grows tall, erect stems lined with fern-like leaves and clusters of white flowers on top.
It spreads by vigorous self-seeding and can form dense colonies of vegetation. This plant typically invades roadsides, fields, pastures, and wetlands, reducing the area’s biodiversity.
Alternative: If you’re looking for a tasty herb for your garden, try parsley (Petroselinum crispum). Parsley is easy to grow from seed, it’s edible, and it is a larval host plant for the black swallowtail butterfly caterpillar. While parsley is not native to the United States, it doesn’t spread invasively, and it’s a great culinary plant.
Dame’s Rocket
Dame’s rocket (Hesperis matronalis) is an herbaceous perennial from Europe. It has been used as a garden flower because it is easy to grow and boasts showy pink or white spring-blooming flowers.
Dame’s rocket spreads rapidly by self-seeding and has widely naturalized in disturbed areas, woodlands, grasslands, and along roadways. It is now listed as an invasive species in several states, particularly in the northeastern region.
Alternative: Garden phlox (Phlox paniculata) is a native perennial wildflower. Hummingbirds and butterflies love the showy, fragrant, spring-blooming flowers.
Dodder
Dodder (Cuscuta japonica) is an annual herbaceous vine. It develops long, thin tendrils with characteristic yellow-orange stems that are particularly noticeable by the end of summer. It is difficult to control, and vines must be pulled before they flower to prevent re-seeding.
This invasive plant produces copious numbers of seeds, forming larger and larger colonies in the Northeast each year. Dodder is parasitic and feeds on host plants through the roots.
Alternative: Golden groundsel (Packera aurea) is a native perennial wildflower with showy yellow flowers that bloom in the spring and summer. This plant makes an excellent ground cover, and the flowers attract pollinators.
English Ivy
English Ivy (Hedera helix) is a familiar landscaping plant commonly sold at garden centers as a ground cover. It is an evergreen vine that covers buildings, fences, and vegetation.
Once established, it becomes quite difficult to remove because it spreads by vigorous stem growth and self-seeding. Any root sections left in the ground will re-sprout and keep growing. This invasive plant has naturalized across the United States and is commonly found in woodlands and urban areas of the Northeast.
Alternative: Creeping phlox (Phlox subdulata) is a native herbaceous perennial wildflower. This plant forms dense clumps and makes a great ground cover for smaller areas. Butterflies and other pollinators visit the showy white, purple, or pink flowers.
Giant Hogweed
Giant hogweed (Heracleum mantegazzianum) may be interesting to look at, but it is a noxious invasive weed native to the Western Caucasus region of Russia. This plant forms thick, woody stems and has large parsley-like leaves. Showy umbels of white flowers bloom in the summertime.
Be very careful while handling this plant, and always wear long sleeves and gloves because touching giant hogweed can cause painful blistering and burning of the skin. Giant hogweed spreads by producing numerous seeds and colonizing roadsides, fields, meadows, and forest edges.
Alternative: Dill (Anethum graveolens) is a showy herb native to northern Africa that is used culinarily and does not spread out of control. Growing dill in your flower garden or herb garden will attract lots of butterflies and pollinators to its showy yellow umbels.
Japanese Angelica Tree
The Japanese angelica tree (Aralia elata) is a deciduous shrub native to eastern Asia. It has long, pinnately compound leaves and clusters of white flowers that bloom in the summertime.
Japanese angelica was imported as an ornamental landscaping plant but has escaped cultivation and is now listed as an invasive plant in several northeastern states. This plant spreads rapidly by self-seeding and root suckers, forming dense thickets that compete with native vegetation.
Alternative: Spicebush (Lindera benzoin) is a native deciduous shrub that grows best in moist, shaded areas. The showy, fragrant flowers attract butterflies in the spring, and the small red berries attract birds in the fall.
Japanese Barberry
Japanese barberry (Berberis thunbergii) is a small to medium-sized deciduous shrub from Japan. It grows well in both full sun and full shade and tolerates a variety of soil conditions. This shrub is often used as an ornamental for hedgerows, where it can be appreciated for its flowers, berries, and colorful foliage.
Birds eat the Japanese barberry fruits, spreading them into nearby fields and forests where they compete with native vegetation. Unfortunately, this plant is now listed as an invasive species in many of the eastern states, particularly in the cooler climate of the Northeast.
Alternative: Shrubby St. John’s wort (Hypericum prolificum) is a deciduous shrub native to the central and eastern United States. Bright yellow flowers bloom in late spring or early summer to brighten your landscape and attract pollinators.
Japanese Honeysuckle
Japanese honeysuckle (Lonicera japonica) is a familiar woody vine from Asia. This plant twines and climbs up trees, fences, and shrubbery, reaching over 30 feet long. This plant was originally introduced as an ornamental vine for its fragrant white flowers, which bloom in the early summer months.
It spreads quickly through vegetative growth and is capable of covering native vegetation and strangling smaller trees. It is most commonly seen in open woodlands and along forest edges.
Alternative: Coral honeysuckle (Lonicera sempervirens) is a climbing vine native to the southeastern United States, although it is cold hardy to zone 4. The bright red tubular flowers are a favorite of hummingbirds.
Mile-a-minute Vine
It’s not too surprising that a plant named “mile-a-minute vine” is invasive. The mile-a-minute vine (Persicaria perfoliata) was introduced from eastern Asia. It grows quickly, smothering vegetation in fields, open woodlands, and along forest edges.
This is an annual vine with triangular leaves and insignificant, small, white flowers. It drops seeds wherever it grows, allowing future generations of rampant growth.
Alternative: Clematis ‘Jackmanii’ (Clematis ‘Jackmanii’) is an extremely showy vine that is not invasive. It grows well on a trellis and produces spectacular large purple flowers each summer.
Moneywort
Moneywort (Lysimachia nummularia) is a creeping ground cover from Europe and southwestern Asia. It’s often used as an easy-to-grow landscaping plant and has naturalized in much of the United States.
It has rounded leaves along fast-growing, branching stems and blooms with showy yellow flowers in the summertime. It thrives in moist, shaded woodlands, meadows, and wetland areas. As it spreads, it forms a dense mat of greenery and competes with native vegetation.
Alternative: Christmas fern (Polystichum acrostichoides) is native to eastern North America. Christmas ferns provide year-round greenery and thrive in rich, moist, shaded woodlands.
Multiflora Rose
Multiflora rose (Rosa multiflora) is a deciduous shrub from Asia. It has become very widespread in the eastern United States and is listed as an invasive species in many northeastern states. Multiflora rose tolerates a remarkable range of conditions and forms dense thickets in fields, pastures, roadsides, and along forest edges, choking out native vegetation.
These plants are thorny and have pink or white flowers that bloom in the summertime. Multiflora rose spreads by root sprouts and self-seeding.
Alternative: Roses (Rosa spp.) are a familiar shrubby perennial with countless varieties of flower types and colors to choose from. Most rose plants are not invasive, and many are surprisingly easy to grow.
Norway Maple
The Norway maple (Acer platanoides) is a deciduous tree from Europe and western Asia. It has been used as an easy-to-grow ornamental tree and is still commonly encountered today.
There are several cultivars of Norway maple, and it’s best to avoid growing any of these plants because they all produce copious quantities of seeds. The seeds then sprout and grow quickly, displacing native vegetation.
Alternative: Red Maple (Acer rubrum) is an easy-to-grow native deciduous tree with beautiful fall foliage. Red maple grows well in moist soil and is very cold-hardy.
Oriental Bittersweet
Oriental bittersweet (Celastrus orbiculatus) is a fast-growing woody vine. It can grow up to 60 feet long and develops a thick woody stem as it wraps its way up trees. It develops an abundance of prominent red-orange fruits that persist on the vine late into fall and winter.
Birds forage on the fruits and deposit seeds throughout nearby forests, wooded edges, fields, and roadsides. Oriental bittersweet easily smothers other trees, shrubs, and vegetation it covers.
Alternative: Climbing hydrangea (Hydrangea anomala subsp. petiolaris) is a large climbing vine native to Asia. Climbing hydrangea blooms in the summertime with fragrant, showy flowers and displays beautiful yellow fall foliage.
Porcelain Berry
Porcelain berry (Ampelopsis brevipedunculata), also known as porcelain vine, is a climbing vine native to Asia. This woody vine closely resembles grapevine and grows to 20 feet or more.
Porcelain berry vines were introduced as easy-to-grow ornamental vines with colorful, showy fruits. Birds and mammals eat the fruits, allowing these invasive plants to spread quickly, invading woodlands and smothering native vegetation in the Northeast.
Alternative: Grape (Vitis labrusca) is a woody vine that will typically tolerate winters up to zone five. Grape vines look great growing on a trellis or along a fence and produce delicious edible fruits.
Princess Tree
The princess tree (Paulownia tomentosa), also known as royal Paulownia, is a medium-sized tree native to China. The large, heart-shaped leaves and showy clusters of pink bell-like flowers earned its place as an ornamental landscape plant.
It has naturalized throughout the eastern United States and is now listed as an invasive species in many states. It spreads readily by seed and has managed to colonize along roadsides, woodland edges, and along waterways.
Alternative: Black tupelo (Nyssa sylvatica) is a tree native to eastern North America. This easy-to-grow tree has spectacular bright red fall foliage.
Privet
Privet (Ligustrum vulgare), also known as common privet or European privet, is a small tree native to Europe, northern Africa, and Asia. It has semi-evergreen foliage and small, white, fragrant flowers. It’s a favored hedge plant because it grows quickly and easily in diverse conditions and creates a dense wall of foliage.
After flowering, the privet produces an abundance of small, round fruits. Birds eat the fruits and distribute seeds throughout the surrounding area. Plants also form dense colonies from root sprouts, competing with native vegetation.
Alternative: The gray birch (Betula populifolia) is an attractive smaller tree native to eastern North America. These plants grow quickly and will spread and naturalize to make attractive privacy shields. You can regularly prune them to maintain an individual tree shape.
Purple Loosestrife
Purple loosestrife (Lythrum salicaria) is an herbaceous perennial imported from Europe as an ornamental flowering plant. You can spy it invading wetlands throughout the northern United States.
Purple loosestrife grows fast and spreads fast, producing prolific quantities of seed. Over time, it forms dense stands in wet ditches, wetland edges, and marshes, sometimes completely displacing native vegetation in the area.
Alternative: New York ironweed (Vernonia noveboracensis) is a perennial wildflower native to the eastern United States. It is easy to grow, particularly in wet soils. The fluffy purple flowers bloom in late summer and into fall, attracting plenty of pollinator activity.
Siebold Viburnum
The Siebold viburnum (Viburnum sieboldii) is a small to medium-sized deciduous shrub native to Japan. Its showy spring-blooming white flowers and colorful fall foliage made it a popular choice in the garden.
Birds eat the fall fruits and help spread this plant into natural areas. It is tolerant of varied growing conditions and has escaped cultivation and naturalized in several northeastern states. It prefers moist soils in open woodlands.
Alternative: Winterberry holly (Ilex verticillata) is a beautiful native shrub that grows to about 12 feet tall. Unlike the evergreen hollies, this holly is deciduous, losing its leaves each winter while displaying spectacular bright red fruits, which often linger on the plant late into the season, providing a valuable food source for birds.
Tree of Heaven
The tree of heaven (Ailanthus altissima) is a deciduous tree originating in China. It has long, compound leaves and large clusters of showy seedpods. Tree of heaven spreads aggressively to form dense thickets, competing with other vegetation in the area.
It produces copious seeds and many root suckers, making it an unappealing landscaping tree. It dominates roadsides and other disturbed habitats in many northeastern states.
Alternative: Oak trees (Quercus spp.) are beautiful native trees that anyone can enjoy. They provide food for wildlife, make great shade trees, and are hardy and easy to grow. Plus, they have attractive fall foliage.
Winged Burning Bush
Winged burning bush (Euonymus alatus), also known as winged euronymus, is a deciduous shrub that comes from Asia. This plant has been used as a landscaping plant for its bright red, showy fall foliage.
Birds eat the copious, small red fruits and disperse the seeds throughout nearby habitats, especially open woodlands, fields, forest edges, and roadsides. Many bushes grow closely together, forming dense thickets that displace native vegetation.
Alternative: Sweet pepperbush (Clethra alnifolia) is an attractive shrub native to eastern North America. Sweet pepperbush blooms in the summertime with dense, showy, white clusters of flowers that birds and butterflies love. This plant makes a great hedge for a partially shaded location.
Wisteria
Chinese wisteria (Wisteria sinensis) is a fast-growing vine native to China. This is a deciduous, woody vine that can grow up to 35 feet long. Its beautiful and fragrant purple flowers are hard to resist.
It spreads aggressively by root suckers and self-seeding and has become a common sight along highways, utility rights-of-way, and around urban areas. Wisteria vines grow thickly, entangling native plants and smothering them with a thick carpet of vegetation.
Alternative: The American wisteria (Wisteria frutescens) is native to the eastern United States. While this plant grows quickly, it is less aggressive than the Asian species. American wisteria has beautiful fragrant purple flowers and is the host plant of the marine blue butterfly.
Yellow Floating Heart
The yellow floating heart (Nymphoides peltata) is a variety of water lily from Europe and Asia. It has showy yellow flowers and has been used as an ornamental pond plant.
It spreads by seed and underwater runners, allowing these plants to cover the surface of still and slow-moving waters, displacing native wetland vegetation. If you are growing these in a private pond, be careful not to transport any part of this plant into nearby waterways.
Alternative: The American white water lily (Nymphaea odorata) is native to the northeastern United States. This beautiful plant produces fragrant white flowers and provides a habitat for wildlife without being aggressive.
Frequently Asked Questions
If pollinators like an invasive plant, should I still avoid it?
Many invasive plants have nectar-rich flowers and attract pollinators. Unfortunately, these invasive plants outcompete and displace native plants and ultimately reduce the natural species diversity of an area. There are plenty of pollinator-friendly plants that are beautiful, easy to grow, low-maintenance, and non-invasive. Native plants are always a great option.
What are some of the benefits of gardening with native plants?
Native plants offer many benefits for the home gardener. They are well adapted to the local climate conditions, they are hardy, and they are very easy to grow. Native plants generally don’t require supplemental watering, pesticides, or extra fertilizers to grow well. Plus, native plants are beautiful and help enhance the natural environment, providing enjoyment for you and valuable food and shelter for the local wildlife.
What’s the difference between an invasive plant and a non-native plant?
Non-native plants originated in another region, country, or continent. Invasive plants are non-native plants whose introduction causes environmental or economic harm or that can pose a risk to human health. Not all non-native plants are invasive.
Final Thoughts
To grow the healthiest and most well-balanced garden, avoid growing plants known as invasive species. Unfortunately, nurseries and garden centers commonly sell several invasive species, so it’s up to you to know the difference. Learn to recognize some of the most common invasive plant species in your region and remove them if they start invading your landscape. When you are choosing plants for your garden, look for species that are not only beautiful but well-behaved. There’s always a good alternative to an invasive plant species!