Creeping Jenny, known scientifically as Lysimachia nummularia, is a common, low-growing perennial plant often used as an ornamental groundcover. This herbaceous species is popular for its ability to quickly form a dense mat of foliage, providing color and texture in various garden settings. Native to Europe and Western Asia, it has become naturalized in many other regions. It is prized for its trailing habit and hardiness across USDA zones 3 to 9.
The Signature Foliage and Stem Structure
The most recognizable feature of Creeping Jenny is its foliage, which is the source of its other common name, Moneywort. The leaves are small, typically ranging from about \(0.25\) to \(1\) inch in diameter, and have a rounded or slightly kidney-shaped appearance, resembling tiny coins strung along the stems. These leaves are arranged in opposite pairs directly along the thin, smooth stems.
The color of the foliage varies depending on the specific cultivar and the amount of sun exposure it receives. The standard species features a soft, bright green color that remains semi-evergreen in milder climates. The most popular form is the ‘Aurea’ cultivar, which displays vibrant golden or chartreuse leaves.
For the ‘Aurea’ variety, the leaves range from light lime green in shadier conditions to a brilliant gold when grown in full sun. The thin stems supporting the foliage are usually light green or sometimes reddish. Inspection of the leaves may reveal tiny, scattered glandular dots that appear dark red or black.
Understanding Its Trailing Growth Pattern
The “creeping” aspect of the plant’s name refers to its prostrate, low-lying growth habit, allowing it to function effectively as a groundcover. Creeping Jenny stems are repent, meaning they trail horizontally along the soil surface, enabling the plant to spread vigorously and colonize an area. Individual trailing runners can extend anywhere from \(1\) to \(2\) feet long.
This vigorous spreading creates a dense, low mat of foliage that typically reaches a height of only \(2\) to \(4\) inches off the ground. The plant’s ability to form this mat relies on its capacity to root at the nodes, which are the points where the leaves attach to the stems. When a node contacts moist soil, it sends out slender, fibrous roots, anchoring the runner and establishing a new plant section.
This characteristic allows it to spread rapidly and makes it an effective choice for filling spaces or cascading over edges, like retaining walls or container sides.
Distinctive Yellow Flowers
While the foliage is the main visual attraction, Creeping Jenny also produces small, cheerful yellow flowers that aid in its identification. These blooms are cup-shaped and typically have five distinct petals. The flowers are relatively small, generally measuring between \(0.5\) and \(1\) inch across.
The blossoms appear singly, emerging from the leaf axils, which are the points where the leaf stems meet the main trailing stem. Bloom time usually begins in late spring and continues intermittently throughout the summer, sometimes lasting into the fall. The flowers of the standard green species are generally more conspicuous than those of the golden ‘Aurea’ cultivar. Although it blooms, the plant primarily relies on its creeping stems to spread.