Ground covers are low-growing plants that spread quickly to form a dense mat, smothering weeds and preventing soil erosion. They provide an attractive, low-maintenance alternative to lawns. However, some aggressive ground covers can become invasive pests that outcompete native plants. When choosing ground covers, it’s important to avoid plants that could harm ecosystems. Here are 5 invasive ground covers to avoid planting in your yard or garden.
English Ivy
English ivy (Hedera helix) is a popular ground cover due to its evergreen foliage and ability to thrive in shade and poor soil conditions. However, it can easily escape cultivation. English ivy is extremely invasive and has spread through natural habitats across much of North America.
English ivy grows rapidly, climbing up trees, fences, and walls. As it ascends, the added weight can cause damage. English ivy competes aggressively with native plants for sunlight, moisture, nutrients, and space. It forms dense blankets that block sunlight from reaching other plants below.
Once established, English ivy is extremely difficult to control. It spreads through rhizomes underground and through seeds spread by birds. Any fragmentation of the vines can lead to new infestations. Vigilant pruning and removal of root systems are required.
To avoid major issues, do not plant English ivy. Seek native alternatives like Virginia creeper, trumpet honeysuckle, or Allegheny pachysandra. If you already have English ivy in your landscape, prune it regularly and remove any vines extending beyond the desired area.
Why English Ivy is Invasive
- Grows aggressively and spreads rapidly
- Climbs up and covers trees and structures
- Forms dense mats that outcompete native plants
- Spreads through rhizomes underground and seeds dispersed by birds
- Evergreen leaves block sunlight from reaching other plants
- Difficult to control once established
Alternatives to English Ivy
- Virginia creeper
- Trumpet honeysuckle
- Allegheny pachysandra
- Sweet woodruff
- Wild ginger
- Foamflower
Periwinkle
There are two types of periwinkle that are highly invasive in North America: common periwinkle (Vinca minor) and bigleaf periwinkle (Vinca major). Introduced from Europe as a popular garden ground cover, these aggressive growers have naturalized throughout much of the U.S.
Periwinkle spreads rapidly to form dense colonies that crowd out native species. It thrives in a variety of conditions including full sun, shade, and poor soils. Once established, periwinkle is extremely persistent and difficult to remove.
The resilient stems root at the nodes as they creep along the ground. Manual removal can leave fragments that take root again. Vigorous digging is required to remove the extensive root system. Chemical control methods may be necessary in severe infestations.
To avoid headaches down the road, skip periwinkle in favor of less aggressive alternatives like lilyturf, wild ginger, or foamflower. If you already have periwinkle, be vigilant about clipping any spreading stems and digging out new colonies.
Why Periwinkle is Invasive
- Aggressive spreading ground cover
- Displaces native plants
- Grows under many conditions – sun, shade, poor soil
- Stems root at the nodes, allowing fragments to spread
- Tough to remove once established due to extensive root system
- Chemical control sometimes needed for severe infestations
Alternatives to Periwinkle
- Lilyturf
- Wild ginger
- Foamflower
- Sweet woodruff
- Carex
- Epimedium
Japanese Honeysuckle
Japanese honeysuckle (Lonicera japonica) is a perennial vine that has become invasive across much of the United States. Introduced as an ornamental for its fragrant flowers, Japanese honeysuckle now chokes out native plants in at least 45 states.
This aggressive vine climbs up trees, shrubs, and fences, girdling stems and restricting light availability. Dense stands of Japanese honeysuckle cover and kill vegetation creating a monoculture lacking biodiversity. It also prevents reforestation by outcompeting tree seedlings.
Birds relish the black berries of Japanese honeysuckle, spreading the prolific seeds far and wide. New plants grow rapidly, gaining up to 6 inches per day. Manual removal is challenging and often ineffective. After cutting or mowing, the plants simply regrow from the extensive root system.
Do not plant Japanese honeysuckle. Instead, consider less invasive honeysuckle species like trumpet honeysuckle (Lonicera sempervirens) or other native vines such as Virginia creeper. Remove established honeysuckle through persistent cutting and targeted herbicide application.
Why Japanese Honeysuckle is Invasive
- Fast growing, climbing vine forms dense thickets
- Girdles and climbs trees and shrubs, restricting light
- Displaces native plants, restricting biodiversity
- Spreads quickly via bird-dispersed seeds
- Extensive root system makes manual removal ineffective
- Resprouts vigorously after cutting or mowing
Alternatives to Japanese Honeysuckle
- Trumpet honeysuckle
- Virginia creeper
- Passionflower
- Clematis
- Hairy honeysuckle
Wintercreeper
Wintercreeper (Euonymus fortunei) is an evergreen ground cover introduced from Asia as a hardy ornamental vine. However, it has become an aggressive invader in forest understories throughout much of the eastern United States.
Wintercreeper spreads rapidly, blanketing the ground and climbing up tree trunks. As it climbs, the added weight pulls down branches and eventually kills trees and shrubs. Dense stands crowd out native plants, damaging wildlife habitat. Birds eat the seeds, accelerating spread.
Once established, wintercreeper is extremely difficult to remove. It grows from small fragments, so any manual removal tends to spread the infestation. The waxy evergreen leaves also resist most herbicides. Combining manual removal and targeted herbicide use provides the best control.
Do not plant wintercreeper. Consider using a native evergreen like partridgeberry instead. Remove existing wintercreeper by hand weeding and disposing of all fragments, followed by careful herbicide treatment of any regrowth. Monitor the area for several years for any new sprouts from the expansive root system.
Why Wintercreeper is Invasive
- Fast-spreading evergreen ground cover
- Climbs and blankets trees and shrubs, restricting light and growth
- Displaces native plants in forest understories
- Grows from small fragments, spreading after removal attempts
- Waxy leaves resist herbicides
- Seeds spread by birds
- Difficult to fully eradicate
Alternatives to Wintercreeper
- Partridgeberry
- Allegheny spurge
- Bearberry
- Creeping phlox
- Wild ginger
Chinese Wisteria
Chinese wisteria (Wisteria sinensis) is a deciduous woody vine introduced from China in the 1800s. Grown for its beautiful cascading flowers, Chinese wisteria has become a problematic invader throughout the eastern U.S.
Chinese wisteria grows at an incredible rate, climbing over trees, shrubs, and buildings up to 66 feet high. As it climbs, it strangles plants and structures, its weight pulling down branches and walls. Dense shade cast by the foliage kills most other plants below.
Removing established Chinese wisteria is extremely challenging. The vines regrow vigorously when cut. The plant produces chemicals that inhibit the growth of nearby plants. To fully eradicate, the entire root system must be killed.
Do not plant Chinese wisteria under any circumstances. For a non-invasive alternative, consider native American wisteria. If Chinese wisteria already exists on your property, removal will require determination and persistence. Cut vines repeatedly and monitor for years until the root system expires.
Why Chinese Wisteria is Invasive
- Very fast growing vine climbs up to 66 ft high
- Climbs over trees, shrubs, and buildings, causing damage
- Displaces native plants through shading and allelopathy
- Regrows vigorously after cutting
- Complete removal requires killing the extensive root system
- Difficult to fully eradicate
Alternatives to Chinese Wisteria
- American wisteria
- Trumpet honeysuckle
- Dutchman’s pipe
- Passionflower
- Virginia creeper
Conclusion
These five aggressive plants highlight why using non-native ground covers can be problematic. What may seem like an attractive, carefree option at first can turn into an invasive nightmare down the road. Always research ground cover plants thoroughly before planting, especially for large areas. Favor native species which are adapted to local conditions.
When tackling existing invasive ground covers, persistence and consistency are key. Aim to fully remove the root systems to prevent regrowth. Monitor areas long-term since seeds and fragments may still germinate in future years. With early intervention and responsible planting choices, you can help prevent ecological harm and avoid major hassles controlling invasive species.
Frequently Asked Questions about Invasive Ground Covers
Below are some common questions and answers about managing and avoiding invasive ground cover plants:
What makes a ground cover invasive?
- Non-native plants that spread aggressively outcompeting native species. They reproduce and spread quickly, have no natural predators, and are difficult to control.
How do I remove invasive ground covers?
- Manual removal by digging, pulling, and excavating the root system. Follow up repeatedly with pruning and monitoring. May also need herbicide application targeting regrowth.
What are some native ground cover alternatives?
- Wild ginger, foamflower, partridgeberry, Virginia creeper, bearberry, Allegheny spurge, sweet woodruff. Consult local resources.
What is the most invasive ground cover?
- English ivy is likely the most problematic. It climbs and blankets trees and spreads aggressively through seeds and underground rhizomes. Extremely tough to control.
How do I prevent ground covers from becoming invasive?
- Favor native species. Research invasiveness before planting. Use containment like borders and paved areas. Prune and weed regularly to maintain desired coverage area.
Can you eat periwinkle?
- No, common periwinkle and bigleaf periwinkle are not edible and are potentially toxic. Do not ingest any part of these invasive ground cover plants.
How do birds spread invasive ground covers?
- Birds eat the berry-like fruits of invasives like English ivy, Japanese honeysuckle, and wintercreeper. Then they spread the seeds through their droppings as they fly and roost far from the parent plant.
In summary, always exercise caution when planting ground covers. Prioritize native species and make sure to maintain any non-natives properly to prevent unchecked spreading. Learn to identify highly invasive species and work to remove them from your landscape and community. With vigilance, you can help protect local ecosystems from these harmful invaders.