Cymbopogon cyanescens Stapf
Cymbopogon cyanescens Stapf, also known as Blue lemongrass, is a perennial herbaceous plant in the Poaceae family. It is native to East Africa and can be found growing in countries such as Kenya, Tanzania, and Ethiopia.
General Appearance
The plant typically grows up to 1.5m tall and has long, slim leaves that are bluish-green in color. The leaves have a lemony scent when crushed, hence the common name "lemongrass." The plant also has small, purple flowers that grow in clusters at the ends of the stems.
Common Names
Aside from Blue Lemongrass, Cymbopogon cyanescens Stapf is also known by other common names such as purple lemongrass, African blue grass, and African wild lemongrass.
Uses
The essential oil extracted from Cymbopogon cyanescens Stapf has been used in traditional African medicine to treat various ailments such as respiratory infections, fever, and stomach problems. The plant is also used in the perfume industry due to its citrus-like scent. In addition, the plant is sometimes used as an ornamental plant in gardens or as a natural insect repellent.
Light Requirements
Cymbopogon cyanescens Stapf requires full sunlight for optimal growth. It cannot thrive in the shade or low light conditions. Therefore, finding a location that gets full sunlight or at least six hours of sunlight is essential for its growth.
Temperature Requirements
The plant thrives in tropical and subtropical climates with temperatures ranging from 20 to 35°C. It requires a minimum daily temperature of 15°C and cannot tolerate extreme cold. In areas with cold winters, it needs to be kept indoors or in a greenhouse during that time.
Soil Requirements
The soil for Cymbopogon cyanescens Stapf should be well-draining, fertile, and rich in organic matter. The ideal pH range for the soil is between 6.0 and 7.5. Sandy loam and loamy soils are the best for the plant. The soil should be moist but not overly wet, as the plant is susceptible to root rot in poorly drained soil.
Cultivation Methods
Cymbopogon cyanescens Stapf, commonly known as Blue lemongrass or Blue mountain lemongrass, can be propagated through seeds and stem cuttings. The plant grows in warm temperatures and requires well-draining soil. It is recommended to choose a sunny location for the plant to ensure its optimal growth. Ensure the plant is protected from frost and cool drafts.
Watering Needs
Water the plant frequently but avoid saturating the soil. The plant requires moist but not waterlogged soil. The frequency of watering may vary depending on the weather condition and soil moisture. It's important to ensure you provide enough water, especially during the hot summer months.
Fertilization
Cymbopogon cyanescens does not require frequent fertilization. Fertilizers such as nitrogen can be applied once a year during the growing season to boost the growth of the plant. However, avoid over-fertilization as it can lead to the production of too much foliage and little oil.
Pruning
Pruning the plant is essential to promote branching and prevent the plant from becoming leggy. It's recommended to prune the plant frequently, especially during the growing season. Cut back the plant to around six inches above the ground level during spring to promote bushy growth. You can use the cut leaves for different culinary purposes.
Propagation of Cymbopogon cyanescens Stapf
There are two primary methods of propagating Cymbopogon cyanescens Stapf: through seeds or through division.
Propagation through seeds
The first step in propagating Cymbopogon cyanescens Stapf through seeds is to collect mature seeds from an existing plant. The seeds should be sown in a potting mix that is well-draining and moist, but not wet. The potting mix should be kept moist until the germination process is complete.
Cymbopogon cyanescens Stapf seeds typically take between one and two weeks to germinate. Once the seedlings have developed at least two sets of true leaves, they can be transplanted to individual containers or larger pots with well-draining soil that is rich in nutrients.
Propagation through division
Cymbopogon cyanescens Stapf can also be propagated through division, which involves splitting an established plant into two or more separate plants. This is typically done in the spring or early summer when the plant is actively growing.
To propagate through division, start by digging up the entire plant, being careful not to damage the roots. The plant can then be gently teased apart into smaller clumps, each with their own roots and stems. Each clump can be repotted into its own container or replanted in a new location.
It's important to note that Cymbopogon cyanescens Stapf is sensitive to changes in its environment, so care should be taken when transplanting or replanting to avoid causing stress to the plant.
Disease Management
Cymbopogon cyanescens Stapf is susceptible to several diseases, including:
- Fungal leaf spot: This disease is caused by several fungi that thrive in humid environments. Symptoms include circular or irregular-shaped spots on the leaves that eventually turn yellow and fall off. To manage this disease, remove all the infected leaves, reduce watering, and ensure proper drainage.
- Root rot: Root rot is caused by the fungi Fusarium and Phytophthora. Symptoms include wilting, stunted growth, and yellowing leaves. Manage this disease by improving soil drainage, avoiding overwatering, and applying a fungicide.
- Mosaic virus: This virus causes yellow mottling on the leaves and stunts growth. To manage this disease, remove infected plants and control aphids, which are the main vectors of the virus.
Pest Management
Cymbopogon cyanescens Stapf is also vulnerable to pest attacks, such as:
- Aphids: These small insects suck sap from the leaves, causing wilting and stunted growth. Control aphids by spraying the plant with a strong jet of water or applying an insecticidal soap.
- Trips: Trips cause tiny, silvery streaks on the leaves and can inhibit plant growth. Control trips by removing any infected leaves and applying a pesticide.
- Caterpillars: Caterpillars chew holes in the leaves and can cause severe damage. Remove any caterpillars by hand and apply a natural or chemical insecticide.
By monitoring the plant regularly and taking prompt action when pests or diseases are spotted, you can protect Cymbopogon cyanescens Stapf and enjoy a healthy plant.
