Botanical Identification of Lemon Grass (Cymbopogon citratus)

To identify Lemon Grass (Cymbopogon citratus) accurately, examine its morphological characteristics, taxonomic classification, and diagnostic features.

Lemon Grass (Cymbopogon citratus) Monograph

Scientific Classification

Lemon grass, or Cymbopogon citratus, belongs to the kingdom Plantae, division Magnoliophyta, class Liliopsida, order Poales, family Poaceae, genus Cymbopogon, and species Cymbopogon citratus. This classification places it within the grass family, highlighting its botanical relationship to other aromatic herbs.

The following table shows the full taxonomy of this plant.

Botanical Nomenclature and Synonyms

Cymbopogon citratus is the scientific name for lemon grass, first described by the botanist Carl von Linné. It is also known by several synonyms, including Cymbopogon flexuosus and Cymbopogon nardus. Common names include lemon grass, citron grass, and mosquito plant, while regional and historical names vary across cultures and regions.

Morphological Characteristics

Lemon grass is an upright perennial herb with a fibrous root system. Its stems are cylindrical and often aromatic, growing up to 1-2 meters tall. Leaves are long, narrow, and grass-like, with a distinct citrus scent. The inflorescence is a dense cluster of small, spike-like flowers. Each flower has three stamens, and the fruit is a small, three-lobed capsule containing tiny seeds.

Diagnostic Identification Features

Lemon grass can be distinguished by its tall, narrow leaves with a distinct citrus scent when crushed. It has a cylindrical, fibrous stalk and narrow, grass-like leaves with a prominent midrib. It differs from similar species like lemongrass (Cymbopogon flexuosus) by its more robust stalk and stronger aroma. Its flowering stems are usually shorter and less branched.

Natural Habitat and Geographic Distribution

Lemon grass is native to tropical regions of Africa, Asia, and the Pacific. It thrives in warm, humid climates with mild winters. It prefers well-drained soils and is commonly found at low to mid-altitudes.

Phenology and Growth Cycle

Lemon grass typically blooms during the summer months, producing small, clustered inflorescences. Seed formation occurs in late summer to early fall. For identification purposes, the plant is best harvested when the leaves are fully developed but before flowering, usually in early to mid-summer.

Phylogenetic Relationships

Lemon grass (Cymbopogon citratus) is closely related to other members of the Cymbopogon genus, which belongs to the Poaceae family. It shares key traits with other grasses, such as narrow leaves and inflorescences, but is distinguished by its aromatic oils and narrow, grass-like foliage. Its phylogenetic placement highlights its relationship to other aromatic grasses used in herbal medicine.