Four o’clocks, also known as Mirabilis jalapa, can indeed be invasive in flower beds. I speak from personal experience as a gardening enthusiast who has dealt with this issue. While they may initially seem like beautiful and easy-to-grow plants, their vigorous growth and heavy seed production can quickly become a problem.
One of the main reasons why four o’clocks can be invasive is their ability to self-sow. As their name suggests, these flowers typically open in the late afternoon and produce seeds throughout the growing season. These seeds can easily scatter and germinate in the surrounding area, leading to a constant cycle of new seedlings each year. This can quickly overcrowd a flower bed and compete with other desired plants for resources such as sunlight, water, and nutrients.
Another factor contributing to their invasiveness is their rapid growth rate. Four o’clocks are known to grow rampantly, quickly spreading through underground rhizomes and forming dense clumps of foliage. This aggressive growth can lead to the plants overtaking other plants in the bed and smothering them. Additionally, the weight of the growing stems and foliage can cause the plants to become top-heavy and fall over, further adding to their invasive nature.
In terms of management, controlling the spread of four o’clocks can be challenging. Regular deadheading of the spent flowers can help reduce seed production and limit their spread. However, it is essential to remove the flowers before they have a chance to set seed. This can be a time-consuming task, especially if you have a large number of plants or a vast area to cover.
Another approach to managing their invasiveness is to dig up and remove the plants entirely. This can be a labor-intensive process, as four o’clocks have extensive root systems, including underground rhizomes. Care must be taken to remove all parts of the plant to prevent regrowth. It may be necessary to repeat this process over several seasons to ensure complete eradication.
If you still wish to enjoy the beauty of four o’clocks without the invasiveness, consider growing them in containers or designated areas where their spread can be contained. This way, you can appreciate their vibrant flowers without worrying about them taking over your garden.
Four o’clocks can be invasive in flower beds due to their ability to self-sow and rapid growth rate. They can quickly overcrowd the space, compete with other plants, and fall over under their weight. Managing their invasiveness requires regular deadheading, digging up and removing the plants, or confining them to containers or designated areas. By being proactive in their control, you can strike a balance between enjoying their beauty and maintaining the integrity of your flower beds.
