Citronella grass, Cymbopogon nardus, is a tropical clumping grass best known for its intense citrus-like scent. It is a close relative of culinary lemon grass with similar long, narrow leaves and cane-like stems. Other common names include blue citronella grass, nard grass, and mana grass. Citronella grass originated in southeast Asia but is now grown deliberately, or has naturalized, throughout much of the tropics. It is commercially grown in many areas for extraction of its aromatic oil, and is also planted as a garden or landscape ornamental in warm climates.
The recommended setting for citronella grass is in full sun on well-drained soil of at least average fertility. It is a perennial from U.S. Department of Agriculture (USDA) planting zone 10 south through the tropics. Citronella grass can also be grown as an annual grass where the growing season is both warm enough and long enough. As it grows, the grass forms a clump often as wide as it is tall, and can reach from 5 to 6 feet (1.5 to 1.8 m) in optimal growing conditions. Citronella grass typically requires at least 30 inches (76 cm) of water per year to thrive.
Citronella grass has naturalized in many places that have suitable year-round temperatures and sufficient rainfall to sustain growth. It spreads most easily in grasslands and open woodland. In parts of tropical Africa it is considered a weed on pasture land and requires a significant effort to control it. Control is complicated by the practice of burning fields for weed suppression. Studies show that citronella grass easily recovers from annual burning and readily spreads by seed into areas previously covered by other plants.
Plant is a perennial, shallowly rooted rhizome. Culms are tufted, robust, up to 2 m tall. Leaf sheaths are glabrous, reddish inside; leaf blades relatively thin, drooping 2/3 of their length, 40-80 cm tall, 1.5 to 2.5 cm wide, abaxial surface glaucous, adaxial surface light green, margins scabrid, base narrow, apex long acuminate. Spathate compound panicle large, lax, up to 50 cm. Sessile spikelets are elliptic-lanceolate; lower glume, flat or slightly concave, 2-keeled, 3-veined between keels.
What Is Citronella Oil?
Citronella essential oil is obtained from the Cymbopogon genus plant family. More precisely, it is extracted through steam distillation of the grassesCymbopogon nardus (Jowitt) and Cymbopogon winterianus (Rendal). This results in two types of citronella oil:
- Ceylon, which is obtained from nardusand is a native product of Sri Lanka (previously Ceylon). Ceylon citronella oil has a warm, citrusy, and wood scent, and has a pale to dark yellow color.
- Java, which is distilled from winterianus. It also has a fresh lemon-like scent but is darker in color. Between the two, java citronella is considered the one with the higher quality.
Chemical Composition of Citronella Essential Oils
Citronella oil contains a number of fragrant fractions of which citronellal, geraniol, and citronellol are the major components. Gas chromatographic analysis of the Ceylon variety indicates that the oil contains large amounts of monoterpenes (approximately 27%), as opposed to the Java variety, which contains only 1% to 3%, mostly in the form of limonene. Both types contain comparable amounts of geraniol (18% to 21%). The Java oil is superior to the Ceylon type; the Java variety contains 16% citronellol and 33% citronellal, whereas the Ceylon type contains only 8% and 5%, respectively. The chemical composition of essential oil can vary tremendously. Other compounds predominant in citronella oil include citronellyl acetate, β bourbonene, geranyl acetate, elemol, L-borneol, and nerol. A geraniol-rich mutant of citronella has been developed; it is reported to have a geraniol content as high as 60%. The wild Ceylon variety (commonly called mana grass) has a chemical profile very different from the 2 cultivated types.
Fractional distillation of Ceylon citronella yielded 13 fractions that were tested against mosquito larvae. Monoterpene fractions containing mycrene were very lethal to late third instar Culex quinquefasciatus larvae. Elemol and methyl iso-eugenol were responsible for larvicidal activity in other fractions.
Below is the summary of the main constituents of each oil
Ceylon Citronella Oil
- Geraniol – 18 to 20 percent
- Citronellal – five to 15 percent
- Citronellol – 6.4 to 8.4 percent
- Geranyl acetate – two percent
- Limonene – nine to 11 percent
- Methyl isoeugenol – 7.2 to 11.3 percent
Java Ceylon Oil
- Citronellal – 32 to 45 percent
- Citronellol – 11 to 15 percent
- Geraniol – 21 to 24 percent
- Geranyl acetate – three to eight percent
- Limonene – 1.3 to 3.9 percent
- Elemol and sesquiterpene alcohols – two to five percent
Health Benefits of Citronella Essential Oil
Apart from being used as a flavoring agent for foods & beverages, it has varied medicinal uses, which are listed below.
Components like methyl isoeugenol and a few others that are found in this essential oil are responsible for this property. They kill bacteria and inhibit any further bacterial growth in the body. This is particularly helpful in treating infections in wounds, as well as in the colon, urethra, urinary bladder, stomach, intestines, urinary tracts, prostate and kidneys.
This oil fights depression and gives relief from anxiety, sadness, and negative feelings. It induces a fresh, happy feeling and hope.
The antiseptic properties of this essential oil fight infections in wounds, as well as the urinary tracts, urethra, prostate and kidneys, while simultaneously protecting them from being sepsis.
It relieves spasms of the muscles, respiratory system and nervous system. It also helps to cure menstrual spasms and gives relief from symptoms such as cramps and coughs.
Citronella essential oil sedates inflammation, particularly those situations which pertain to the liver, stomach, intestines and other parts of the digestive system. The inflammations caused as side effects of drugs, excessive use of alcohol or narcotics, hard & spicy food, any disease, or any toxic element getting into the body can also be soothed using this oil.
The crisp, rich citrus or lemon-like aroma of this oil drives away body odor and is used in deodorants and body sprays, although in very small quantities, since in heavy doses it may create skin irritations. It can also be mixed with bath water to have a refreshing, body odor-ending bath.
The diaphoretic properties of this essential oil increase sweating and promote the removal of toxins and other unwanted materials like excess water, fat and salts from the body. This makes the body feel lighter, keeps the skin healthy and also reduces fever. This also protects you from certain infections.
The increase in the frequency and quantity of urination due to this property of citronella essential oil has many benefits. It disposes of waste substances and toxins from the body, including uric acid, excess bile, acids, and salts, as well as water and fats. This helps reduce weight, eliminate infections in the urinary system, free the body from toxins, reduce chances of renal calculi, rheumatism and arthritis, improve digestion, and keep the heart healthy.
While the diaphoretic property of this oil increases perspiration, it anti-inflammatory property reduces inflammation while the antimicrobial property fights infections. The combined effects of these three properties fight fever and reduce body temperature.
This oil kills fungus and inhibits fungal growth. This is very useful in countering fungal infections in the ear, nose and throat region. Contracting fungal infections in the ears is very common and can be very serious. It eliminated fungal infections in other parts of the body as well and helps cure fungal dysentery.
11.) Insect Repellant
This is one of the most commonly used properties of this essential oil, as it kills and keeps away insects. It has been found particularly effective on a species of mosquito, called Aedes Aegypti whose bite causes the dreaded Yellow Fever. This is also effective on lice, body and head louse, and fleas.
The use of this oil clears the stomach from infections and other problems and helps it function properly.
The stimulating effect of the essential oil of citronella stimulates blood circulation, secretions and discharges like hormones and enzymes from the glands, brain while also increasing activity in the nervous system. This essential oil also stimulates the immune mechanisms and the metabolism of the body.
This property means that citronella essential oil has an overall toning effect on the body. It tones up digestion, excretion, the nervous system and the brain, while fortifying the body.
Citronella essential oil kills intestinal worms. It should be administered in mild doses to children, since children are most prone to worms. It is effective on both round worms and tape worms. Since the presence of worms interferes with the normal physical and mental growth and also with the absorption of nutrients by the body, the use of this oil can greatly increase your quality of life by eliminating those dangerous parasites.
Other Benefits: Furthermore, this oil can be used in treatment of problems like oily skin, oily hair, abnormal palpitations, colitis, migraine, neuralgia, fatigue, headache, nausea, and abdominal pain resulting from gas or cramps
Uses of Citronella Oil
- Citronella oil is popularly used as an insect repellent. In fact, the Environmental Protection Agency (EPA) classifies it as a biopesticide with a non-toxic mode of action. Citronella oil can be found in dozens of registered pesticide products, such as sprays, lotions, and candles. At times, it is added to sunscreen, wristbands, and flea collars. Due to its antifungal properties, citronella oil is also used to treat insect bites.
- Citronella essential oil is one of the most common oils used in aromatherapy. It is said that as an aromatherapy oil, citronella can help treat and prevent colds, fevers, and headaches.As a massage oil, it may relieve pain in individuals suffering from arthritis.
- The oil of citronella is also widely used in fragrances and personal care products. It is largely imported by Germany and France, two of the largest hubs for the perfume industry. Because of its antiseptic properties, citronella oil is also used in soaps, household cleaners, and detergents.
- Citronella oil is also added as a food and beverage flavoring, such as in alcoholic drinks, frozen dairy, and gelatin and puddings
- Alcoholic and non-alcoholic beverages
- Baked products
- Frozen dairy
- Gelatin and puddings
- Soft and hard candies
- Additional research found that using citronella oil can help calm barking dogs.
At present, the world production of citronella oil is approximately 4,000 tonnes. The main producers are China and Indonesia – producing 40 percent of the world’s supply. The oil is also produced in Taiwan, Guatemala, Honduras, Brazil, Sri Lanka, India, Argentina, Ecuador, Jamaica, Madagascar, Mexico, and South Africa.
The market for natural citronella oil has been eroded by chemicals synthesised from turpentine derived from conifers. However, natural citronella oil and its derivatives are preferred by the perfume industry.
How to Make Citronella Oil
Citronella oil is widely available in in natural food and beauty stores. However, commercial oils processed through steam distillation may be pricey. A more practical solution would be to make your own citronella oil at home,
There are sites that provide step-by-step guides on how to create citronella oil. Here is one from eHow.com:
- ¼ ounce nard grass leaves and stems (you may use lemongrass as substitute)
- 1 cup olive oil
- Slow cooker (ex. Crock-Pot)
- Mix the olive oil and nard grass leaves and stems in the slow cooker.
- Leave and cook the mixture for about four to eight hours.
- With the cheesecloth, strain the mixture, which is actually the citronella oil. Remove nard grass.
- Repeat steps 1-3 with the strained mixture with fresh nard grass leaves and stems. No need to add more olive oil. Keep on repeating until the oil obtains the desired scent.
- Once done, seal the oil in a dark-colored jar. Store in a cool, dry place.
You can also purchase ready made Citronella Essential oils here.
Citronella oil is Generally Recognized as Safe (GRAS) by the US Food and Drug Administration (FDA). The EPA also considers oil of citronella safe, as it has very little or no toxicities. If ingested, the major compounds of citronella are eliminated through urination.
As I said earlier, avoid using pure citronella oil on your skin. Not only can this oil cause skin irritations or allergic reactions in people with sensitivities, it has been found to raise heart rate in some individuals.
Pregnant women should be careful with using citronella oil, as their skin is extra sensitive during those nine months. One research found that there was a loss of spontaneous contractions in the uterus upon the in vitro use of citronella oil. While citronella may be used cautiously as a fragrance during this time, it is important to consult a physician first.
Also, citronella oil should not be used on babies and young children due to their delicate skin. Parents should also be careful when administering the oil near the noses of children. Seek the advice of your pediatrician before using citronella oil on your children.