Lemongrass: History and Traditional Use
Lemongrass is a plant with two quite different histories folded into one. The first is a kitchen and cottage history: a tropical grass, Cymbopogon citratus, pounded into Thai and Vietnamese curry pastes, stuffed inside a Filipino roast, and brewed into a bedtime tea from Jamaica ("fever grass") to Brazil (capim-santo). The second is an industrial history few tea-drinkers know: for the first half of the twentieth century, lemongrass oil from the Malabar coast of India was the world's main source of citral, the lemon-scented aldehyde from which chemists made violet perfume and, from 1947, synthetic vitamin A. This article follows both threads, from the naming of the grass to the Kerala oil boom, the chemists of the 1890s, and the Brazilian trial of 1986 that tested the calming tea on people and found no effect. Where the record is firm we say so; where it is folklore or thin, we say that too.
Table of Contents
- Origins, Botany, and a Tangle of Relatives
- Naming the Grass: From Andropogon to Cymbopogon
- Kitchen and Folk Medicine in South and South-East Asia
- Indian Tradition and the Sanskrit Record
- Across the Tropics: Fever Grass and Capim-Santo
- The Oil Trade: From the Philippines to the Kerala Boom
- Citral, Ionone, and Vitamin A: The Chemists' Chapter
- Tradition Under Test: The Modern Studies
- Official Recognition and the Living Tradition
- Lemongrass Today
- Key Research Papers
- Connections
- Featured Videos
Origins, Botany, and a Tangle of Relatives
Lemongrass is a tall, clump-forming perennial grass of the genus Cymbopogon, a group of roughly fifty to sixty aromatic grasses spread across the warm parts of Asia, Africa, Australia and the Pacific. The plant most of the world cooks with is Cymbopogon citratus, known in the trade as West Indian lemongrass. Its close relative Cymbopogon flexuosus, the East Indian, Malabar or Cochin lemongrass, is native to India, Sri Lanka, Burma and Thailand, grows taller, flowers freely, and has always been the main source of the distilled oil. The two are used interchangeably in many places, but they are distinct species with different histories: C. citratus is the food and tea plant, C. flexuosus the industrial crop.
Where C. citratus itself came from is genuinely uncertain, and it is worth being honest about that. The Royal Botanic Gardens, Kew list its native range as southern India and Sri Lanka; Indian agricultural authorities generally assume a Malesian origin, in the islands of maritime South-East Asia; and Otto Stapf, the botanist who gave the plant its modern name, wrote in 1906 that it was not known in the wild at all, only in cultivation. The plant itself is to blame: cultivated lemongrass rarely flowers and is propagated by dividing the clump, so it has travelled the tropics as cuttings for centuries and left no clear trail of wild populations. The safest statement is the general one: lemongrass is a plant of tropical South and South-East Asia, domesticated so long ago that its wild ancestor has been lost.
The genus also contains three relatives that are constantly confused with lemongrass, and the confusion runs through old herbals and modern shop shelves alike. Citronella is the oil of Cymbopogon nardus (Ceylon citronella) and Cymbopogon winterianus (Java citronella); its scent is dominated by citronellal and geraniol rather than citral, and it is the mosquito-repellent grass, not the cooking one. Palmarosa is Cymbopogon martinii, whose rose-scented oil is mostly geraniol. Lemongrass proper is defined by citral: a good oil of either lemongrass species is 70–85 percent citral, which is why it smells so unmistakably of lemon. Throughout this article, "lemongrass" means the two citral grasses, and the relatives are named when they enter the story.
Naming the Grass: From Andropogon to Cymbopogon
Lemongrass reached European botany late and sideways. In Species Plantarum (1753) Linnaeus described two aromatic grasses of the group under the genus Andropogon — Andropogon nardus, the citronella grass, and Andropogon schoenanthus, the "camel grass" of the ancient Near East — but the culinary lemongrass of South-East Asia was not among them. It entered the formal record only in 1813, when the Swiss botanist Augustin Pyramus de Candolle listed it as Andropogon citratus in his catalogue of the Montpellier botanical garden, the name simply recording its lemon scent.
The genus Cymbopogon was proposed in 1815 by the German botanist Kurt Sprengel. The name is Greek: kymbe, a boat, and pogon, a beard, describing the boat-shaped bracts (spathes) and the hairy, bearded flower spikes that distinguish these grasses when they do flower. For most of the nineteenth century, however, the oil-grasses stayed under Andropogon in a tangle of duplicate names. The East Indian species was separated as Cymbopogon flexuosus by W. Watson in 1882, in a botanical account of the Himalayan districts of India's North-Western Provinces.
Order was finally imposed in 1906. Otto Stapf, the Austrian-born botanist at Kew, published The Oil-Grasses of India and Ceylon in the Kew Bulletin of Miscellaneous Information, sorting the commercially important grasses into Cymbopogon (ten species), Vetiveria and Andropogon, and transferring de Candolle's plant to give the name still used today, Cymbopogon citratus (DC.) Stapf. The parenthetical "DC." credits de Candolle's original description; "Stapf" records the transfer. Stapf wrote the paper for a practical reason: the Indian essential-oil trade needed to know which grass produced which oil.
Kitchen and Folk Medicine in South and South-East Asia
Long before any botanist named it, lemongrass was a staple of the kitchens of mainland and island South-East Asia, and it remains one. In Thailand it is takhrai, the essential aromatic of tom yum and tom kha kai, pounded in a tall mortar with galangal, garlic and makrut (kaffir) lime leaf into the curry pastes at the heart of the cuisine. In Vietnam it is sả, the marinade herb of grilled pork and chicken (thịt nướng sả, gà nướng sả) and a companion to chilli in many braises. In Indonesia and Malaysia it is sereh or serai, one of the foundations of the spice pastes called bumbu, alongside galangal, turmeric and shallots. In the Philippines it is tanglad, and its most famous role is not in a sauce at all: whole stalks are stuffed into the cavity of lechon, the celebratory roast pig, so that the meat perfumes itself from the inside as it turns over the coals. Cambodian, Lao, Burmese and Sri Lankan cooking use it in the same spirit.
Folk medicine followed the kitchen. Across the region lemongrass tea has traditionally been taken for fevers and colds, for stomach cramps, wind and indigestion, and as a mild calming drink, and the bruised leaves or oil rubbed on for aches and as an insect deterrent. These are traditional uses, recorded as such: they tell us what people believed and did, not what the plant has been proved to do. Their consistency across so many separate cultures is itself the historical fact worth noticing.
Indian Tradition and the Sanskrit Record
India's relationship with lemongrass is old, but it is easy to overstate how precisely it is documented. Indian and Sri Lankan sources give the grass Sanskrit names, bhustrina among them, and later trade names such as "Indian verbena" and "Indian melissa oil", and describe a long tradition of using the leaf infusion for fever, coughs, colds and digestive complaints, and the oil rubbed on for rheumatic pain. A Sri Lankan literature survey states that lemongrass has been used in Indian medicine for more than two thousand years. We have not been able to confirm a specific passage in the classical Ayurvedic compendia, the Charaka Samhita or Sushruta Samhita, that unambiguously refers to this grass rather than to a relative, so this article makes no such attribution. What can be said with confidence is that by the nineteenth century, when British and Indian pharmacognosists were cataloguing the subcontinent's materia medica, lemongrass and its oil were established folk remedies in the south, and that the East Indian species is genuinely native to the Malabar coast where the oil industry would later grow.
Across the Tropics: Fever Grass and Capim-Santo
Because it grows from a division of the clump in almost any warm soil, lemongrass was one of the plants that moved easily along the colonial shipping routes of the eighteenth and nineteenth centuries, and it took root in every tropical colony it reached. One literature survey dates its introduction to Jamaica to 1799; whatever the exact year, by the nineteenth century it was thoroughly naturalised in the Caribbean, where it acquired the name it still carries there: fever grass. Across the islands a hot infusion of the leaves became the household remedy for fevers, colds, an upset stomach and frayed nerves, and it remains one of the best-known "bush teas" of the region; the Caribbean pharmacopoeia project TRAMIL lists it among the islands' documented traditional remedies.
In Brazil the plant became something close to a national herbal tea. It is known by a small cloud of names — capim-santo ("holy grass"), capim-limão, capim-cidreira, capim-cidró, capim-cidrão — the "cidreira" names borrowed from erva-cidreira, the Portuguese name for lemon balm, because the two plants smell alike and were used for the same thing: a soothing infusion for nerves, poor sleep and cramps. The Brazilian infusion is traditionally an abafado, dried leaves steeped covered so that the aroma does not escape, and it is drunk in the evening. That sedative reputation is the one Brazilian pharmacologists would put to the test in the 1980s (see below).
Lemongrass reached Spanish America too, as té de limón or zacate de limón, and tropical Africa, where it is grown from Cameroon to Tanzania as a tea and fever remedy. Everywhere it went, it kept the same three jobs: a drink for fever, a drink for the stomach, and a drink for the nerves.
The Oil Trade: From the Philippines to the Kerala Boom
The second history of lemongrass begins when someone first put the leaves in a still. The standard literature reports that the earliest record of lemongrass oil being distilled comes from the Philippines in the seventeenth century, during the Spanish period, and that the oil was exported from there in small quantities. The primary document behind this statement is not well identified in the sources we could check, so we report it as the received account rather than as an established fact.
The industry that mattered grew up on the Malabar coast of south-west India, in the princely states of Travancore and Cochin, today's Kerala. Systematic cultivation and distillation of the East Indian grass there began around the end of the nineteenth century, and the oil, shipped through the port of Cochin, became known worldwide simply as "Cochin oil". The growers were smallholders and estate owners who planted the grass on poor upland soil where little else paid and distilled it in simple field stills. By the interwar years lemongrass covered tens of thousands of acres in Kerala, and after the Second World War it had the status of a plantation crop.
The peak came in the early 1950s. Indian government sources record that India was then producing more than 1,800 tonnes of lemongrass oil a year and held a near-monopoly of world production and trade; next to Mysore sandalwood oil it was the country's most important essential-oil export. Two forces broke the monopoly. One was competition: Guatemala had begun growing West Indian lemongrass in the 1930s, expanded fast when the Second World War cut the Allies off from Asian supplies, and never gave the market back. The other, as the next section explains, was chemistry: the industry that bought most of the world's lemongrass oil learned to make its key ingredient without the grass. India's output fell to a few hundred tonnes a year, and today Guatemala, India and China share a much smaller market, the Indian product still traded as "Cochin" oil and the Guatemalan as "West Indian".
Citral, Ionone, and Vitamin A: The Chemists' Chapter
Until 1888 nobody knew what lemongrass oil was made of. In that year chemists in the laboratory of a German essential-oil house isolated its principal constituent, an aldehyde of ten carbon atoms, C10H16O, and named it citral for its lemon smell. (An aldehyde is a small reactive molecule with a carbon–oxygen double bond at its tip; the aldehyde group is what makes citral so easy to build other molecules from.) The American chemist F. D. Dodge described the same compound from lemon-scented gum oil shortly afterwards under the name "citriodora aldehyde", and in 1891 Friedrich Wilhelm Semmler showed that it was identical to geranial, the aldehyde obtained by oxidising geraniol. Later work by Barbier and Bouveault in France and by Ferdinand Tiemann in Berlin settled that natural citral is in fact a pair of mirror-arranged isomers, citral-a and citral-b, which we now call geranial and neral. Every bottle of lemongrass oil is mostly these two molecules.
The discovery that made lemongrass an industrial crop came in 1893. Ferdinand Tiemann — already famous for synthesising vanillin — and his co-worker Paul Krüger were hunting the scent of violets, one of the most prized and most elusive notes in perfumery. In a paper titled Ueber Veilchenaroma ("On Violet Aroma"), published in the Berichte of the German Chemical Society, they reported that condensing citral with acetone and treating the product with acid gave a compound that smelled powerfully of violets. They called it ionone, from the Greek for violet. Ionone was the first great synthetic perfume material, and its raw material was citral — which meant lemongrass oil.
Then ionone acquired a second life. One of its two forms, beta-ionone, contains the six-membered ring that sits at one end of the vitamin A molecule, and from the 1930s chemists trying to synthesise vitamin A used it as their starting point. The first successful syntheses were reported in 1947: by the Dutch chemists Jozef Arens and David van Dorp, and, in the same year, by Otto Isler and colleagues in Switzerland, whose route — published in Helvetica Chimica Acta as Synthese des Vitamin A — became the basis of the first industrial production. Both began with beta-ionone, and beta-ionone began with citral, so for a period after the war the vitamin A in a capsule could be traced back to a field of grass in Travancore. The dependence did not last: natural citral was scarce and variable, the shortage had already slowed vitamin A research during the war, and chemists soon found routes to citral and beta-ionone from petrochemical feedstocks. Once citral could be made in a factory, the grass lost its most important customer — the deeper reason the Indian boom of the 1950s ended.
Alongside citral, the oil carries smaller amounts of geraniol, geranyl acetate, limonene and myrcene. The leaf infusion, by contrast, contains only a little of the volatile oil and is richer in water-soluble flavonoids — a distinction that matters when reading the studies that follow.
Tradition Under Test: The Modern Studies
The most instructive chapter in lemongrass's scientific history was written in São Paulo. In the early 1980s a group led by the pharmacologist Elisaldo Carlini set out to test the country's most popular calming tea with the same rigour a drug would receive, and published the results as a three-part series in the Journal of Ethnopharmacology in 1986. Parts I and II tested the tea on laboratory animals, including two months of daily dosing in rats, and found no toxicity. Part III, by José Roberto Leite and colleagues, is the one that matters most: the abafado of dried leaves was given to healthy volunteers as a single dose and then daily for two weeks, with a full panel of blood and urine tests, an electrocardiogram and an electroencephalogram. It was, in the authors' words, "atoxic" — no meaningful change in any measure. Then fifty volunteers took lemongrass or a placebo double-blind and reported on their sleep, and eighteen people with high trait anxiety took lemongrass or placebo before an anxiety-provoking test. Neither experiment found any effect: sleep was the same on lemongrass as on placebo, and the anxious volunteers were exactly as anxious. The authors concluded that lemongrass tea, "one of the most popular Brazilian herbal medicines, used for its alleged CNS-depressant effects, is atoxic but lacks hypnotic or anxiolytic properties."
That is a negative result, and it deserves to be reported as one. It remains, forty years on, the most careful human trial of lemongrass tea for sleep and anxiety, and a model of taking a tradition seriously enough to test it properly.
The story did not end there, because later researchers changed the question. In 2011 a Brazilian group showed that lemongrass essential oil — not the tea — produced anxiety-reducing behaviour in mice that was blocked by a drug interfering with GABA, the brain's main calming neurotransmitter. In 2015 a small study in humans found that simply inhaling lemongrass aroma before an anxiety-inducing test reduced anxiety scores and tension compared with a control odour. Neither contradicts Leite's 1986 finding: a cup of tea contains very little volatile oil, whereas the oil and its aroma deliver citral directly. The honest summary is that the sedative tradition is unsupported for the tea as traditionally drunk, and modestly supported, in animals and in one small aroma study, for the concentrated oil.
The strongest modern evidence for lemongrass lies elsewhere, in the laboratory dish. Since the 1990s lemongrass oil and citral have repeatedly proved potent against bacteria and fungi in vitro, including Candida yeasts, and the reviews of 2011, 2015 and 2022 catalogue antimicrobial, antioxidant and insect-repellent activity across dozens of experiments. Human trials remain small and few; test-tube activity is a real finding about the oil, not evidence that drinking the tea treats an infection.
Official Recognition and the Living Tradition
Lemongrass never acquired a German Commission E monograph or a European Union herbal monograph, and it is absent from the WHO's volumes of selected medicinal plants; in Europe and North America it has been regulated as a food flavouring and a fragrance ingredient rather than as a medicine. Its official standing is strongest where its tradition is strongest. In Brazil, Cymbopogon citratus leaf appears in the Formulário de Fitoterápicos da Farmacopeia Brasileira, the herbal formulary of the national pharmacopoeia, first published in 2011 and revised in 2021. The monograph specifies an infusion of one to three grams of dried leaf in 150 mL of water, steeped five to ten minutes, and lists the traditional indications — as an antispasmodic for mild menstrual and intestinal cramps and as an aid for mild anxiety and insomnia — while warning against use in pregnancy, in children and with sedative drugs. It is a recognition of tradition and safety, not a claim that the tea has been proved to work.
The lesson of the regulatory record matches the lesson of the science. Lemongrass is one of the safest herbs in common use as a food and a tea; the one human safety study found nothing amiss, and centuries of daily drinking across three continents agree. The concentrated oil is a different substance — a potent antimicrobial and a skin irritant that must be diluted and is never taken by mouth — and every tradition that used the oil used it externally.
Lemongrass Today
Walk through any city with a South-East Asian community and you will find lemongrass twice over: fresh stalks in the greengrocer's crate and citral in the air of the soap aisle. Its culinary reach has grown enormously since the 1970s, when Thai and Vietnamese restaurants spread across the West and took tom yum and lemongrass chicken with them; the stalk is now grown in Florida, Queensland and southern Europe and sold in supermarkets everywhere, and the tea has travelled from the bush-tea traditions of the Caribbean and Brazil onto herbal-tea shelves worldwide. The oil industry survives, smaller than in its 1950s heyday, with Guatemala, India and China the main producers.
What has not changed in four centuries of records is the plant's modesty. Lemongrass has never been a heroic drug or a famous cure. It is a grass that makes food taste brighter, a tea that people across the tropics reach for when they feel unwell or unsettled, and — for one remarkable half-century — the raw material from which chemists conjured the scent of violets and the first synthetic vitamin. That is history enough.
Key Research Papers
The list below combines the modern reviews of lemongrass ethnobotany and pharmacology, the genuine historical landmarks of citral chemistry, the 1986 Brazilian human trial and its animal companions, and the later anxiety studies discussed in the article. Historical primary texts (de Candolle's 1813 catalogue, Stapf's 1906 Oil-Grasses of India and Ceylon, the Brazilian formulary) are named in the article as historical sources rather than cited here. Each external link opens in a new tab.
- Shah G, Shri R, Panchal V, Sharma N, Singh B, Mann AS (2011). Scientific basis for the therapeutic use of Cymbopogon citratus, stapf (Lemon grass). Journal of Advanced Pharmaceutical Technology & Research. — PubMed PMID: 22171285
- Ekpenyong CE, Akpan E, Nyoh A (2015). Ethnopharmacology, phytochemistry, and biological activities of Cymbopogon citratus (DC.) Stapf extracts. Chinese Journal of Natural Medicines. — PubMed PMID: 25986281
- Avoseh O, Oyedeji O, Rungqu P, Nkeh-Chungag B, Oyedeji A (2015). Cymbopogon Species; Ethnopharmacology, Phytochemistry and the Pharmacological Importance. Molecules. — doi:10.3390/molecules20057438
- Tibenda JJ, Yi Q, Wang X, Zhao Q (2022). Review of phytomedicine, phytochemistry, ethnopharmacology, toxicology, and pharmacological activities of Cymbopogon genus. Frontiers in Pharmacology. — doi:10.3389/fphar.2022.997918
- Tiemann F, Krüger P (1893). Ueber Veilchenaroma. Berichte der deutschen chemischen Gesellschaft. — doi:10.1002/cber.18930260373 (the discovery of ionone from citral)
- Tiemann F, Semmler FW (1893). Ueber Verbindungen der Citral-(Geranial-)reihe. Berichte der deutschen chemischen Gesellschaft. — doi:10.1002/cber.18930260374
- Isler O, Huber W, Ronco A, Kofler M (1947). Synthese des Vitamin A. Helvetica Chimica Acta. — doi:10.1002/hlca.19470300666 (the beta-ionone route to synthetic vitamin A)
- Carlini EA, Contar J de DP, Silva-Filho AR, da Silveira-Filho NG, Frochtengarten ML, Bueno OF (1986). Pharmacology of lemongrass (Cymbopogon citratus Stapf). I. Effects of teas prepared from the leaves on laboratory animals. Journal of Ethnopharmacology. — PubMed PMID: 3762195
- Leite JR, Seabra M de L, Maluf E, Assolant K, Suchecki D, Tufik S, Klepacz S, Calil HM, Carlini EA (1986). Pharmacology of lemongrass (Cymbopogon citratus Stapf). III. Assessment of eventual toxic, hypnotic and anxiolytic effects on humans. Journal of Ethnopharmacology. — PubMed PMID: 2429120 (the human trial: no toxicity, no hypnotic or anxiolytic effect)
- Costa CA, Kohn DO, de Lima VM, Gargano AC, Flório JC, Costa M (2011). The GABAergic system contributes to the anxiolytic-like effect of essential oil from Cymbopogon citratus (lemongrass). Journal of Ethnopharmacology. — PubMed PMID: 21767622
- Goes TC, Ursulino FR, Almeida-Souza TH, Alves PB, Teixeira-Silva F (2015). Effect of Lemongrass Aroma on Experimental Anxiety in Humans. Journal of Alternative and Complementary Medicine. — PubMed PMID: 26366471
PubMed Topic Searches
- PubMed: Lemongrass ethnobotany and traditional use
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- PubMed: Lemongrass sedative and anxiolytic studies