11 Perennials You Should Never Grow in Your Yard, According to Horticulturists

Kudzu

Famous for its invasiveness, kudzu can damage native ecosystems as it outcompetes local vegetation and harms the environment. Tammy Sons, founder and CEO at TN Nursery, suggests Creeping Jenny as a safe alternative to kudzu. "This plant features a ground-cover growth and is not nearly as aggressive," she says. "It's not invasive, and will add beauty without overwhelming any surrounding plants."

Bamboo

Another invasive species that spreads aggressively is bamboo. "They often overtake nearby plants and crack sidewalks or foundations," says Chris Turner, owner and landscape designer at Elevate by Design. "Managing its growth requires constant maintenance, and it can become a huge headache."

Turner suggests planting miscanthus or feather reed grass instead, as they both provide a similarly airy look, but are much easier to control.

Japanese Spirea

Japanese spirea can very quickly naturalize an area and crowd out native plants, says Nicole Dillon, a micro-flower farmer and owner at Breemar Flower Farm. "It creeps into meadows and open forest areas, and the seeds dropped from spirea can persist in the soil for several years, making control difficult," she says. "If you like the pink umbels of spirea, consider Joe Pye weed instead. It's native, and comes in many different heights to fit pretty much any garden space."

Norway Maple

Norway maples are invasive and produce shallow, dense root systems that outcompete nearby plants for nutrients and water. "They’re notorious for creating dry, bare patches under their canopy," says Turner. "Plant a red maple instead. It has a stunning fall color and supports native ecosystems."

Purple Loosestrife

If your garden has more of a wetland look, Sons warns against purple loosestrife as an addition. Aquatic ecosystems are in danger of overcrowding with this plant around, and any plants that grow food or provide shelter for wildlife will be wiped out.

"Alternatively, a more beautiful plant that will not harm your space but gives a similar feel would be Joe Pye weed," says Sons. "This is a beautiful native flowering plant that attracts pollinators, rather than forcing them away. It thrives easily in any moist environment without harming the local ecosystem."

Chinese Wisteria

While Chinese wisteria is beautiful and aromatic when in bloom, it has a habit of climbing trees. "Unfortunately, it will eventually choke the trees and kill them," says Dillon. "Plant American wisteria, Coral honeysuckle, or Carolina jessamine instead."

Periwinkle

While the purple flowers can be striking en masse, periwinkle will crowd out other plants in your flower beds. "If your space gets some sunlight, I also really love creeping phlox for a ground cover," says Dillon. "It’s semi-evergreen, and the flowers come in a variety of colors, including periwinkle blue."

Japanese Knotweed

Japanese knotweed is extremely invasive and can even penetrate through concrete. "It has the ability to pierce through foundations and can harm the home," says Sons. "It's very hard to get rid of once it begins, and can harm the ecosystem, just like kudzu can."

Sons recommends creeping thyme instead. "This plant grows low and forms dense mats,” she says. “It's not invasive and can tolerate foot traffic."

Nandina

Nandina is common in American landscapes, but many U.S. states have added it to the invasive species list. "There are many other native plants that also produce beautiful red berries, such as native hollies and winterberry," says Dillon. "Yellow twig dogwoods also provide striking color in the winter garden."

Privet

Privet is almost indestructible, according to Dillon, and forms dense thickets, making it impossible for native plants to grow alongside it. "The leaves also contain compounds that our native insects aren’t adapted to eat," she says. "If you’re looking to screen an area, consider native viburnums, elderberry, or native holly."

English Ivy

English ivy was the top choice to avoid on every expert’s list. "It may look interesting, but it is indeed invasive," Sons says. "This plant climbs and chokes trees, causing significant damage to branches or trunks. It also encourages the spread of fungal diseases and illness to other plants around it."

Dillon warns against picking up this common plant. "It's widely sold in stores, and I see it everywhere in winter planters," she says. "If you don't keep the vine trimmed or you transfer the plant to the ground, it can be a real nightmare to try and get under control later. It can kill trees and even damage your home if you allow it to grow there." 

Sons suggests choosing Boston ivy instead. "It's a similar vine that's completely non-invasive and provides a comparable aesthetic appeal to any space with its vibrant fall colors," she says.