Creeping Myrtle is a perennial evergreen groundcover. It forms dense mats of foliage and flowers, but it does not possess the mechanisms required for true climbing. Unlike vines such as ivy or grapes, Creeping Myrtle lacks specialized structures like tendrils, twining stems, or adhesive rootlets to actively ascend vertical surfaces. Its growth is fundamentally horizontal, confirming its classification as a trailing subshrub rather than a climbing plant.
The Trailing Growth Habit
The primary mechanism Creeping Myrtle uses to expand is a trailing growth habit, meaning its stems lie along the ground. These trailing stems, often called runners, spread outward, typically extending 1 to 1.5 feet per year under favorable conditions. The stems are characterized by nodes, which are points where new leaves and potential roots develop. When a stem node makes firm contact with the soil, it initiates a process known as nodal rooting. Adventitious roots emerge from the node, anchoring the stem to the ground and forming a new, independent plantlet. This continuous rooting and spreading allows the plant to form large, clonal colonies, creating a thick carpet that effectively suppresses weeds. Its ability to quickly cover ground and stabilize soil makes it highly effective for erosion control on slopes.
Why Creeping Myrtle Sometimes Appears to Climb
While Creeping Myrtle does not actively climb, it can give the visual impression of upward growth due to specific environmental conditions and terrain. Any vertical movement is passive, relying entirely on supportive structures rather than on the plant’s own attachment capabilities. The stems have the capacity to grow outward and slightly upward, reaching a height of about three to six inches. When planted atop a low retaining wall or a raised garden bed, the stems will cascade downwards, but they will also attempt to grow over the edge. As the runners drape down, they can then grow back up the face of the structure, especially if the surface is rough or has crevices where the stems can lean for support. This visual effect, where the plant appears to be growing up a wall, is merely a result of the plant filling a three-dimensional space. Similarly, Creeping Myrtle can grow up and over low-lying objects or other nearby plant stems, a behavior that can be problematic for smaller, delicate neighbors.
Managing Vertical Growth and Spread
Controlling the spread of Creeping Myrtle is often necessary. Because the plant spreads through nodal rooting, gardeners must focus on containing the lateral growth of the stems. Installing physical barriers, such as metal or plastic edging buried at least six inches deep, can effectively prevent runners from rooting in unwanted areas.
Regular pruning is a practical method to manage its spread and prevent it from mounding too high. Trimming the trailing runners back to the desired boundary line two or three times a year will restrict its expansion. It is important to remove the cut stems completely. Any discarded piece of stem with a node can potentially root and establish a new plant if left on the soil. For areas where the plant is encroaching on turf or other plants, carefully digging up and removing the rooted sections is the most effective way to maintain clear borders.