As a gardening and landscaping expert, I have encountered periwinkle plants in various climates and I can say that while they may not be considered fully invasive in harsh northern climates, they can certainly become a nuisance in mild climates where they have the opportunity to thrive and spread rapidly.
Periwinkle, also known as Vinca minor, is a low-growing evergreen ground cover that produces beautiful purple flowers. It is often used in garden beds and borders to add a splash of color and create a dense carpet-like effect. However, if not properly maintained, periwinkle can indeed take over grass and other plants in the garden.
One of the reasons periwinkle can be problematic is its ability to spread through underground stems called stolons. These stolons allow the plant to send out roots and establish new plants wherever they touch the soil. If left unchecked, periwinkle can quickly form a thick mat that smothers grass and other vegetation, making it difficult for them to survive.
To prevent periwinkle from taking over grass, it is important to be proactive in managing its growth. Here are some strategies that can be employed:
1. Regular maintenance: Keep a close eye on your garden and regularly remove any periwinkle plants that are encroaching on grass or other desired plants. This can be done by hand-pulling or carefully digging up the plants, making sure to remove as much of the underground stolons as possible.
2. Edging and barriers: Install physical barriers such as edging or plastic borders to create a clear separation between the periwinkle and the grass. This will help prevent the stolons from spreading into the lawn area.
3. Mulching: Apply a layer of mulch around the base of grass and other plants to create a barrier that inhibits the growth and spread of periwinkle. Mulch also helps retain moisture and suppress weed growth, giving grass a better chance to compete with periwinkle.
4. Regular mowing and trimming: Keep the grass well-maintained by regularly mowing and trimming it at the appropriate height. This will help discourage the periwinkle from spreading into the lawn area and maintain a healthy grass cover.
5. Herbicides: In extreme cases, where periwinkle has already taken over a large area of grass, the use of selective herbicides specifically designed to target broadleaf plants like periwinkle can be considered. However, it is important to carefully follow the instructions and guidelines provided by the manufacturer to ensure safe and effective use.
In my personal experience, I have seen instances where periwinkle has indeed taken over grass and created a challenging situation for homeowners. However, by implementing the strategies mentioned above and staying diligent in managing its growth, it is possible to control periwinkle and prevent it from completely overtaking the grass.
It is worth noting that periwinkle can still be a valuable addition to a garden when properly managed. Its ability to form a dense ground cover can help suppress weeds and reduce erosion in certain areas. However, it is crucial to strike a balance and maintain control over its growth to prevent it from becoming invasive and overwhelming other desirable plants.
While periwinkle may not be considered fully invasive in harsh northern climates, it can become a problem in mild climates where it has the opportunity to spread rapidly. By implementing proper maintenance practices, such as regular removal, barriers, mulching, and regular mowing, it is possible to prevent periwinkle from taking over grass and maintain a healthy and balanced garden.
