Cymbopogon nardus (L.) Rendle, commonly known as Citronella Grass, is a tropical perennial that thrives outdoors in USDA hardiness zones 9 to 11. It belongs to the Poaceae (Gramineae) family of plants under the classification Cymbopogon.
This plant comes from tropical areas of Asia (e.g., Southeast Asia, Singapore, India, Vietnam) as well as South Sudan and South Africa.
- Cymbopogon Nardus Care
- How To Propagate Citronella Grass?
- Cymbopogon Nardus Pest Or Diseases
- Suggested Mosquito Grass Uses
- Recommended Reading
Cymbopogon nardus is a perennial in a tropical setting, but it can be kept as an annual or as a houseplant in colder settings. It may also be overwintered or kept entirely as a houseplant.
You may also hear this plant referred to as:
- Mosquito Plant
- Mosquito Grass
- Citronella Grass
The reference to mosquitoes is that the plant contains a great deal of the essential oil citronella, a natural mosquito repellent.
However, it is important to note that even though this plant looks quite a bit like Lemongrass (Cymbopogon citratus), it is not the same.
Additionally, even though it is often referred to as Mosquito Plant, this is an inaccurate common name. Mosquito Plant is actually a type of scented geranium.
In this article, we describe and discuss the care of Cymbopogon nardus. Read on to learn more.
Cymbopogon Nardus Care
Size And Growth
Mosquito Grass is a fast-growing grass that grows in clumps, attaining heights of over 8′ feet with a spread of about 4′ feet.
It typically tops out at about 6′ feet tall when kept as a houseplant.
Flowering And Fragrance
The plant has smooth, wide, green strap-like leaves with a reddish base.
Mosquito grass may produce pale pink or tan blooms in a conducive tropical setting during summer and early autumn. However, it is very unlikely to bloom when kept as a houseplant.
Light And Temperature
Cymbopogon nardus prefers a semi-shade setting but also does well in bright, indirect sunlight for 6 to 8 hours daily. In addition, its leaves may be burned by harsh, direct sunlight.
This plant is winter hardy in USDA hardiness zones 9 to 11 and can tolerate temperatures ranging from 30° to 90° degrees Fahrenheit when planted in the landscape.
These plants should be brought indoors or protected against temperature extremes when planted in containers.
Watering And Feeding
Citronella Grass likes slightly moist soil, but it must never stand in water. Instead, use a soak and dry watering method.
When the top couple of inches of soil feels dry, water thoroughly. Do not water again until the top few inches of soil feel dry.
This plant is not a heavy feeder. An annual feeding of slow-release fertilizer in the early spring should be plenty to keep it happy all year round.
However, you may not need fertilizer if you keep the plant as a houseplant and repotting with fresh, new, high-quality potting soil in the early spring.
If you do not repot or use a slow-release fertilizer, use a half-strength balanced fertilizer (5-5-5 or 10-10-10) monthly throughout the growing season (spring and summer); however, this is not really necessary.
Established perennial plants like fertilizer with a bit more nitrogen in a tropical landscape, so look for an NPK ratio such as 10-5-5 or 20-10-10.
Soil And Transplanting
Citronella Grass likes light, loose, well-draining, loamy, slightly acidic soil.
If you keep it as a houseplant, you must repot it annually in the springtime. Be sure to use a container that provides ample room for growth and drainage.
When repotting container plants, gently tamp the soil mixture around the roots to eliminate air pockets and establish good root contact.
Take care not to compact the soil. Water the plant thoroughly once it is repotted.
When planting into the landscape, prepare a hole a couple of inches deeper than needed for the root ball. It should be about twice the width of the root ball.
Prepare a bed of coco coir or compost in the bottom of the hole to provide a rich, well-draining foundation.
Surround the plants’ roots with a combination of the native soil and an amended garden mix as described above. Tamp the soil down lightly, water thoroughly, and add more soil as needed.
Grooming And Maintenance
Trim back dead or damaged leaves as needed to maintain a tidy appearance.
Because this tropical plant likes relatively high humidity (40% to 70% percent), you may need to use a humidifier to prevent leaf browning in houseplants.
How To Propagate Citronella Grass?
The best way to propagate this plant is through division, and this is best done in the early spring.
If you are keeping your plant as a houseplant when you repot you can divide the roots and pot up the sections in their own pots.
If you are keeping your Citronella Grass in the landscape, when it becomes crowded or spreads in areas where you don’t want it, simply dig it up, divide the roots and replant it or pot it up as you wish to create more plants.
Cymbopogon Nardus Pest Or Diseases
This plant is generally pest and disease-resistant; however, it will become subject to problems such as root rot and fungus gnats if you overwater.
To avoid this, ensure well-draining soil, establish a consistent soak-and-dry watering schedule, and never allow your plants to stand in water.
Here are some things you need to remember:
- Lack of humidity may cause leaf tips to turn brown.
- Too little light may cause leaves of Cymbopogon Nardusto to stretch and droop.
- Excessive sunlight may cause leaf burn.
Is Cymbopogon Nardus Considered Toxic Or Poisonous To People, Kids, Or Pets?
The citronella oil contained in the plant is a natural insect repellent. Generally speaking, the oil can be used topically to repel mosquitoes.
However, some people have an allergic reaction to it. Therefore, use caution when applying citronella oil directly to your skin.
Citronella oil should never be consumed; if the plant is eaten, it can be toxic to people, pets, and wildlife.
Consuming large quantities may cause symptoms such as:
- Muscle weakness
Luckily, the properties of Cymbopogon grass that make the oil repellent to mosquitoes also make it unpalatable, so it is unlikely that people, pets, or wildlife will consume it.
Is Cymbopogon Nardus Considered Invasive?
Because this grass does not spread by rhizomes, it is not considered invasive; however, it is a fairly aggressive plant and may compete with lower-growing plants, which may die out in its shade.
Therefore, carefully plan when planting Cymbopogon Nardus in conducive outdoor settings to prevent it take over your garden.
Suggested Mosquito Grass Uses
Mosquito Grass is beneficial when planted around porches, patios, poolside, and other settings where people may sit in the evening. Its natural lemon scent repels mosquitoes.
The essential oils of this plant are anti-carcinogenic, anti-bacterial, and anti-fungal and have many medical uses.
It is also used in both commercial and folk medicines addressing a wide variety of conditions, such as:
- Muscle tension
- Muscle spasms
The oil may also be incorporated into candles to provide mosquito-repellent properties and is often added to cleaning products.
Cymbopogon nardus is grown and harvested commercially for all of these useful purposes.