Creeping Myrtle is a popular groundcover, often sought after for its ability to form a dense, lush carpet of green foliage quickly. Homeowners and landscapers value its rapid spread and reliable evergreen nature, which provides color even through winter months. However, the plant’s vigorous growth habit can quickly become a challenge for gardeners. This guide will clarify the plant’s true identity, detail how to recognize it, and provide effective strategies for managing its aggressive growth.
The True Identity of Creeping Myrtle
The common name “Creeping Myrtle” is confusing because the plant is not a true member of the Myrtle family (Myrtaceae). The plant is Vinca minor, more accurately known as Periwinkle or Lesser Periwinkle. It belongs to the Dogbane family (Apocynaceae), a classification it shares with plants like Mandevilla and Oleander.
The use of “Myrtle” stems from the plant’s small, glossy, evergreen leaves, which superficially resemble those of the true Myrtle species, Myrtus communis. This misnomer creates challenges for gardeners trying to accurately research the plant’s care requirements or control methods. The correct botanical name, Vinca minor, is the most reliable way to ensure you are dealing with this specific, low-growing groundcover.
Visual Identification and Preferred Growing Conditions
Vinca minor is a low-growing, trailing sub-shrub that typically reaches a height of only three to six inches. Its stems, known as runners, trail along the ground and root at the nodes wherever they make contact with moist soil. This rooting mechanism allows the plant to spread quickly and form large, dense mats.
The leaves are evergreen, opposite on the stem, and have a distinctive glossy, dark green appearance with a thick, leathery texture. They are generally small, measuring between 3/4 inch to 1.75 inches long. The flowers appear prominently in the spring, usually from early to mid-spring, and may bloom intermittently into the summer and fall. These solitary, five-petaled flowers are typically a beautiful violet-purple or blue-lavender color, which is how the color “periwinkle” got its name.
This plant is highly valued for its adaptability, thriving across USDA Hardiness Zones 4 through 9. It is particularly successful in areas with deep shade or dappled sunlight, though it can tolerate full sun, especially in cooler climates. Vinca minor is not overly particular about soil, growing well in loamy, sandy, or clay soils, provided they are well-drained. Its ability to tolerate poor, dry soils and dense shade contributes significantly to its success as a groundcover.
Managing Aggressive Growth and Spread
The same characteristics that make Vinca minor an effective groundcover also make it prone to aggressive, invasive growth. Its extensive root system and ability to root at every node make complete eradication challenging once a large patch is established. Containing its spread requires consistent effort and a multi-pronged approach that targets both the foliage and the root system.
Manual removal involves digging out the patches, which is most effective when the plants are small. Gardeners must be meticulous, as any segment of the trailing stem left in the ground can re-root and start a new colony. Regularly cutting the runners and pruning the edges of the growth helps contain the plant within desired boundaries. For large areas, mowing the patches on a high setting suppresses growth and limits its ability to flower and spread.
Where the plant has spread into unwanted areas, chemical control may be necessary, but this requires specific attention to the plant’s waxy leaves. These leaves are designed to shed water, which reduces the effectiveness of many water-based herbicide sprays. Systemic herbicides containing an active ingredient like glyphosate are often used for targeted removal. They should be applied carefully according to label instructions to avoid damaging surrounding vegetation. Applying herbicides in the spring or fall when the plant is actively growing is the most effective timing for absorption.
Physical Containment
Physical containment is the most proactive way to manage its spread in garden settings. Installing physical barriers, such as deep edging or landscape borders, helps prevent the runners from rooting outside of the designated area. Reducing fertilizer and water in established patches also discourages the vigorous growth that leads to rapid spreading.