Lemongrass (Cymbopogon citratus) is a versatile plant, prized for its distinct citrusy aroma in culinary applications and elegant appearance in gardens. Its popularity often leads to confusion with other plants sharing a similar growth habit or fragrance. This article clarifies how to identify authentic lemongrass and differentiate it from common look-alikes.
Characteristics of True Lemongrass
Lemongrass forms a dense, clumping perennial grass, typically growing 2 to 4 feet tall and wide. Its long, narrow, blade-like leaves are light green to yellowish-green, gracefully arching to create a fountain-like appearance. The stalks have a bulbous, pale green to yellowish-white base that gradually tapers into the long leaves. When bruised or crushed, the leaves and stalks release a strong, clean, lemony, and slightly earthy aroma.
Common Culinary Look-Alikes
Citronella Grass (Cymbopogon nardus or Cymbopogon winterianus) is often mistaken for true lemongrass due to their close botanical relationship and similar appearance. Citronella grass typically grows taller, potentially reaching up to 6 feet tall and 4 feet wide, with leaves that can be wider than those of true lemongrass. Citronella Grass often has reddish or magenta-colored stem bases, whereas true lemongrass stems are typically green. While both possess a lemon-like fragrance, the scent of Citronella Grass is generally stronger, sharper, and more pungent, commonly associated with insect repellents rather than culinary use.
Common Ornamental Look-Alikes
Several ornamental grasses visually resemble lemongrass but are cultivated for their aesthetic appeal. Liriope (Liriope muscari), also known as lilyturf or border grass, forms dense clumps of strap-like, arching, dark green leaves, growing 12 to 18 inches tall. It produces spikes of violet-purple flowers in late summer, followed by black berries.
Mondo Grass (Ophiopogon japonicus) is another common ornamental, forming arching clumps of narrow, linear, dark green, grass-like leaves, usually 8 to 12 inches tall. This plant, often used as a groundcover, may produce small, bell-shaped, white to lilac flowers and blue-black berries. Fountain Grass (Pennisetum species) typically forms a graceful, arching clump of foliage with distinctive bottlebrush-like flower plumes that emerge in late summer. Various sedges (Carex species) also resemble grasses with linear or strap-shaped leaves and clumping habits, but they belong to a different plant family and often feature triangular stems.
How to Distinguish Them
The most reliable way to differentiate true lemongrass from its look-alikes is by its distinct aroma. When a leaf or stalk base of true lemongrass is crushed, it emits a clear, bright, and sweet lemony-citrus scent with subtle earthy undertones, suitable for cooking. In contrast, Citronella Grass, while also lemony, has a more medicinal, strong, and sharp fragrance, often described as more citronella-scented than purely lemony. Ornamental grasses like Liriope, Mondo Grass, Fountain Grass, and sedges typically lack any significant citrus scent or possess a grassy, non-aromatic smell.
Beyond scent, examining the physical characteristics provides further clues. True lemongrass has relatively smooth, often sharp-edged leaves and a distinct, firm, pale base that gradually widens. Citronella Grass can have reddish or magenta coloration at its base. Ornamental grasses often have different leaf textures, such as the glossy, strap-like leaves of Liriope or the finer, more delicate blades of some Fountain Grass varieties. The growth habit can also vary; while many are clumping, subtle differences in how they spread or the presence of flowers and berries can help distinguish them.