# Plant Monograph: Lemongrass
**Name of plant:**
Lemongrass
**Catch phrase (Carmina Gadelica or traditional invocation if available):**
No specific invocation to lemongrass is recorded in the *Carmina Gadelica*. A fitting traditional association is found in its Southeast Asian culinary and medicinal traditions: **“The fragrant grass”** — a reference to the plant's strongly aromatic leaves and stems. No historically attested Gaelic blessing specific to lemongrass is known.
**Family:**
Poaceae — the grass family
**Genus and species:**
*Cymbopogon citratus* (DC.) Stapf
**Other names:**
Lemongrass; Lemon grass; West Indian lemongrass; Cymbopogon; Fever grass; Sweet rush; Sereh; Serai; Tanglad; Takrai; Citronella grass (a name sometimes confusingly applied to related *Cymbopogon* species).
**Brief introduction:**
Lemongrass is a strongly aromatic perennial tropical grass native to South and Southeast Asia and now cultivated throughout tropical and subtropical regions. It forms dense clumps of long, narrow, blue-green leaves and produces a characteristic lemon fragrance from its essential oil, which is particularly concentrated in the leaves and lower stems.
The plant has an exceptionally important culinary and medicinal tradition across South and Southeast Asia. It is used in Thai, Vietnamese, Cambodian, Indonesian, Malaysian, Sri Lankan and Indian traditions as both food and medicine. Traditional applications include digestive complaints, feverish illnesses, respiratory symptoms, pain, menstrual discomfort and nervous tension.
Unlike lemon balm, which belongs to the mint family, lemongrass is a true grass. Its characteristic aroma comes principally from **citral**, a mixture of the closely related aldehydes geranial and neral.
**Traditional uses:**
* As a warm aromatic tea for digestive discomfort, indigestion and abdominal bloating.
* Traditionally used for feverish conditions and as a cooling or febrifuge preparation.
* Used for respiratory complaints, including coughs and congestion.
* Used traditionally for menstrual discomfort and as an antispasmodic herb.
* Used as a general aromatic and stimulating herb in food, beverages and household medicine.
**Historical use:**
* Lemongrass has a long history of culinary and medicinal use in South and Southeast Asia, particularly in Thailand, Indonesia, Malaysia, Cambodia, Vietnam and India.
* Ayurvedic and regional South Asian traditions employed aromatic *Cymbopogon* species for digestive, febrile and respiratory complaints.
* In Indonesian traditional medicine, *Cymbopogon* preparations have been used as aromatic digestive and diuretic remedies.
* Lemongrass became an important culinary herb in Southeast Asian cuisine, where its stalks are bruised, sliced or pounded to release their volatile oils.
* Its essential oil subsequently became important in perfumery, flavouring and commercial aromatherapy, although essential oil preparations are substantially more concentrated than traditional culinary preparations.
**Parts used and method of use:**
* Fresh or dried leaves.
* Lower stalks and leaf bases.
Used as:
* Infusion or herbal tea.
* Culinary herb in soups, curries, sauces and rice dishes.
* Decoction or traditional medicinal beverage.
* Essential oil or aromatic preparation; medicinal essential-oil use requires substantially greater caution than ordinary culinary use.
**Use in healing (modern herbal practice):**
* Traditionally and currently used as a digestive and carminative herb.
* Used as a mild antispasmodic for abdominal discomfort.
* Used traditionally for fever and minor febrile illnesses.
* Investigated for antimicrobial and antifungal activity.
* Investigated for antioxidant, anti-inflammatory and analgesic effects.
Modern evidence is considerably stronger for **laboratory and animal pharmacology** than for clinical efficacy in humans. Lemongrass should therefore be regarded principally as a traditional medicinal and culinary herb rather than an established treatment for disease.
**Pharmacology and biochemistry:**
* **Citral** — principally geranial and neral; the major contributor to lemongrass's characteristic lemon fragrance and a major pharmacologically active component of its essential oil.
* **Geraniol, myrcene and citronellal** — volatile terpenoid constituents contributing to the plant's aromatic and biological activity.
* **Flavonoids and phenolic compounds**, including luteolin derivatives and caffeic/ferulic-acid-related compounds.
Mechanisms:
* Citral and related volatile constituents demonstrate **antimicrobial activity** in laboratory studies, including activity against selected bacteria and fungi.
* Experimental studies indicate modulation of inflammatory pathways and oxidative stress, providing a possible basis for observed anti-inflammatory and antioxidant effects.
* Essential-oil constituents may influence smooth-muscle activity and nociceptive pathways, providing a plausible pharmacological basis for traditional antispasmodic and analgesic use.
**Overall profile:**
Lemongrass is primarily an **aromatic carminative, antispasmodic and antimicrobial herb**, with additional experimental antioxidant, anti-inflammatory and analgesic activity. Citral is its defining phytochemical. Traditional medicinal use is extensive, but human clinical evidence remains comparatively limited and does not justify treating lemongrass as a replacement for established medical therapy.
**Common dosage:**
* **Infusion:** approximately 1–2 g dried herb per 150–250 mL hot water, traditionally taken 1–3 times daily.
* **Fresh herb tea:** approximately 5–10 g freshly chopped leaves or stalks per cup, prepared as an infusion or decoction.
* **Culinary use:** fresh stalks or leaves according to taste and recipe; culinary quantities are generally considerably lower-risk than concentrated medicinal preparations.
* **Essential oil:** medicinal internal dosing should **not be extrapolated from culinary use**; concentrated essential oil should only be used internally under appropriate professional supervision.
**Safety factors (including side effects):**
* Culinary use of lemongrass is generally well tolerated, but concentrated medicinal preparations have a substantially different risk profile.
* Excessive oral consumption may cause gastrointestinal irritation, nausea, dizziness or other nonspecific adverse effects.
* Pregnancy and breastfeeding warrant caution with medicinally concentrated preparations because adequate safety evidence is lacking.
* Essential oil can cause skin irritation or sensitization, particularly when applied undiluted.
* Long-term medicinal use of concentrated preparations has not been adequately studied; ordinary culinary use should not be equated with prolonged high-dose supplementation.
**First aid / adverse reaction response:**
* **Mild gastrointestinal upset:** discontinue the preparation, allow symptoms to settle, and seek medical advice if symptoms persist or become severe.
* **Skin irritation after essential-oil exposure:** remove contaminated clothing and wash the affected area thoroughly with soap and water; seek medical attention for persistent or severe reactions.
* **Allergic reaction:** discontinue use; seek urgent medical assistance for facial swelling, breathing difficulty or rapidly progressing symptoms.
* **Accidental ingestion of concentrated essential oil:** do not induce vomiting; contact a poison-control service or seek urgent medical advice, particularly if a significant quantity was swallowed.
**Drug interactions:**
* **Diabetes medications:** experimental evidence suggests lemongrass may influence glucose metabolism, so concentrated preparations could theoretically enhance glucose-lowering effects.
* **Diuretics:** traditional diuretic effects could theoretically be additive with pharmaceutical diuretics.
* **Sedative medications:** experimental CNS effects raise the possibility of additive sedation with concentrated preparations.
* **General interaction considerations:** evidence for clinically significant interactions in humans is limited; caution is particularly appropriate with concentrated extracts and essential oil rather than normal culinary use.
**Horticultural requirements:**
* USDA / Canadian zone: **USDA Zones 9–11** as a perennial; grown as an annual or overwintered indoors in colder Canadian climates.
* Soil pH: **approximately 5.0–8.0**, preferably mildly acidic to neutral, fertile and well drained.
* Light requirements: **Full sun**.
* Moisture: **Consistently moist but well-drained soil**; avoid prolonged waterlogging.
* Other notes (growth habit, harvest timing, etc.):
* **Growth habit:** Large clumping perennial grass, commonly reaching approximately 1–1.5 m in cultivation, with long narrow aromatic leaves.
* **Flowering/fruiting:** Flowering is uncommon in cultivation outside warm tropical climates; plants are primarily propagated vegetatively.
* **Harvest timing:** Outer leaves and stalks can be harvested throughout the growing season; stalks are particularly useful once they have developed substantial basal thickness.
* **Habitat:** Tropical and subtropical regions, especially cultivated gardens, agricultural fields and areas with warm temperatures and adequate moisture.
* **Propagation/cultivation notes:** Easily propagated by division or by rooting fresh stalks. In Canada, plants can be grown in containers and brought indoors before frost. Provide strong light, warmth and adequate moisture during overwintering. Regular harvesting encourages vigorous new growth.
**Sampling of clinical reports / studies:**
* **Clinical study:** Small human studies have investigated lemongrass preparations for anxiety, sleep, pain and other conditions, but the clinical literature remains limited and heterogeneous.
* **Pharmacological study:** Experimental research consistently demonstrates antimicrobial, antioxidant, anti-inflammatory and analgesic activity in lemongrass extracts and essential oil, with citral frequently identified as an important contributor.
* **Phytochemical study:** Chemical analyses identify citral (geranial and neral) as the characteristic major volatile component, accompanied by myrcene, geraniol and other terpenoids.
* **Ethnobotanical evidence:** Traditional medicinal use across South and Southeast Asia is extensive, particularly for digestive complaints, fever, respiratory symptoms, menstrual discomfort and as a general aromatic beverage.
* **Overall assessment of evidence:** **Strong traditional and ethnobotanical foundation; substantial laboratory pharmacology; limited but developing human clinical evidence.** Lemongrass is well established as a culinary and aromatic medicinal herb, while claims for treating specific diseases require considerably stronger clinical evidence.
**Note for the monograph collection:**
Lemongrass is worth distinguishing carefully from **citronella grass (*Cymbopogon nardus* and *C. winterianus*)**. The plants are related and both produce lemon-scented essential oils, but they are not interchangeable medicinally or botanically. *C. citratus* is principally the culinary and medicinal lemongrass used throughout Southeast Asian cuisine, whereas citronella grasses are especially associated with commercial insect-repellent essential oil.
Educational Use Only: The information presented on this page is provided for educational, historical, and informational purposes only. ArdNemeton na Tuatha and Bhùth Draoi do not provide medical advice. Always consult your physician and pharmacist before using any herb, mushroom, supplement, or botanical product for medicinal purposes. Traditional uses described herein do not constitute medical claims.