The name “citronella” refers to two entirely different plants: a true grass that provides the commercial oil and a scented-leaf geranium often sold in garden centers. The answer to whether a citronella plant produces flowers depends entirely on which plant you are examining. Distinguishing between the two requires examining their physical characteristics, especially the type and visibility of any flowers.
Citronella Grass The Source of the Oil
The original citronella plant is a tropical perennial grass of the Cymbopogon genus (C. nardus or C. winterianus). This grass is the source of the essential oil, famous for its strong, lemony fragrance. It grows in dense, tall clumps, often reaching five to eight feet with long, narrow foliage. As a member of the Poaceae family (true grasses), citronella grass technically produces flowers. These flowers form in a narrow, branching cluster called a panicle, rising above the plant. The individual flowers are extremely small, inconspicuous, and described as creamy-white spikelets. When grown as an annual outside of its native tropical habitat, the plant rarely matures enough to display this flowering structure.
The Scented Geranium Often Called Citronella
The second plant commonly marketed as “citronella” is the scented geranium, Pelargonium citrosum, often nicknamed the “Mosquito Plant.” This plant is a bushy, mounded sub-shrub, typically growing two to three feet tall. Unlike the grass, it features soft, deeply lobed or lacy foliage resembling a maple leaf. This geranium produces flowers that are far more noticeable and ornamental than those of the true grass. The blooms appear in small, airy clusters, showcasing shades of pink, lavender, or light purple, sometimes with dark maroon markings. These colorful flowers are clearly visible from late spring through fall.
Visual Differences Between the Two Plants
The primary distinction between the two plants lies in their growth habit and leaf structure. The true Cymbopogon is a tall, coarse, upright grass with thin, sharp, blade-like leaves. The Pelargonium is a bushy, mounded plant with soft, heavily textured, and deeply divided leaves. Both plants share a strong citrus scent when their leaves are brushed, which contributes to the confusion.
The difference in their flowers serves as the ultimate visual identifier. The grass produces small, pale, straw-like spikelets that are often absent outside of tropical conditions. Conversely, the geranium readily produces small but distinctly pink or purple blossoms that are easily seen. Therefore, if a plant labeled “citronella” has visible, colorful blooms, it is the scented geranium, not the essential oil-producing grass.