The butterfly bush may look innocent, but this flowering shrub is guilty of displacing native plants in the Pacific Northwest. In fact, butterfly bush, which quickly forms thickets that crowd out local favorites like willows, is actually banned in the state of Washington.
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English ivy is a popular vining plant that spreads quickly both horizontally and vertically, covering bald patches of ground or softening brick facades. There's a downside to all that growing power: Ivy can easily get out of hand, clinging to everything in sight, including tree trunks, shrubs, and other plants. If you must plant ivy in your yard, you'll need to monitor its growth and aggressively cut it back to prevent it from crowding out other plants and invading the surrounding areas.
These marsh plants with bright purple flowers tend to blanket wetland areas. But don't let their good looks fool you! These dramatic bloomers, considered an invasive species in much of the Northeast and Northwest, choke out local water-loving plants.
Creeping jenny, also called moneywort, is a great-looking ground cover with bright-green leaves and yellow blossoms. It grows well in both sun and shade, so it's no wonder that creeping jenny is a popular choice for gardens. But like many vining plants, it can be invasive in the more humid regions of the United States.
This charming vine can thank its yellow and white flowers for its sweet smell. The bitter truth, however, is that honeysuckle can rapidly take over your yard—and your neighbor's as well. It spreads so successfully both underground through rhizomes and above ground through its seeds and berries that it's considered invasive in the South and Northeast United States.
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Banks of beautiful purple flowers drape gracefully from this climbing vine, making it an attractive choice for landscaping. But in the sun-drenched Southern states, Chinese wisteria can grow like crazy, crowding out neighboring species and potentially taking over a porch or house with its woody vines.
This savory-scented plant was introduced to the United States as a culinary herb. Since then, growers have discovered that the plant is virtually resistant to New World pests or diseases, allowing it to invade woodland and floodplain environments through much of eastern North America.
The barberry's colorful leaves have long made it a favorite in residential and commercial plantings, so you may not know that it's actually a fast-growing menace. The shrub spreads by both seed and root and is considered an invasive plant throughout North America. Barberry's popularity as a hedge may be waning; it has been outlawed in many areas.
These popular trees line many a street, but the Norway maple’s signature “helicopter” seeds can fly far and wide, planting themselves in wooded areas where they can quickly overrun native trees. Admired for their majestic fall foliage, these maples were planted widely before people realized they were invasive.
The brilliant color of this bright-red bush has made it a landscaping standout, and it's still sold in many garden centers despite the fact that it’s considered an invasive species throughout the United States. Oh, and did we mention it’s poisonous?
Give the special gardener in your life a little love this holiday season! Go now to see Bob Vila's best gifts for green thumbs.