Origin
Digitaria gayana (Kunth) A.Chev. ex Stapf, commonly known as Rhodes grass, is a type of perennial African grass that originated in eastern and southern Africa.
Common Names
Rhodes grass is known by various common names, including African grass, bluegrass, Rhodesian grass, and star grass.
Uses
Rhodes grass is commonly used for forage and hay production due to its high-quality nutritional value. It is also used for erosion control, as a cover crop, and in waterway protection due to its deep root system. Additionally, Rhodes grass is used as a lawn grass in some parts of the world.
General Appearance
Digitaria gayana is a tufted grass that can grow up to 2 meters tall. It has flat and narrow leaves that are about 15-30 cm long. The seed head is a panicle that can grow up to 40 cm long and bears spikelets about 2 mm long. The grass has a deep root system that helps it to tolerate drought conditions.
Growth Conditions for Digitaria gayana
Light: Digitaria gayana requires full sun exposure for optimal growth. It is not shade-tolerant and should be grown in an area where it can receive at least 6 hours of direct sunlight each day.
Temperature: This plant is native to tropical and subtropical regions and requires warm temperatures to thrive. The ideal temperature for optimum growth of Digitaria gayana is between 27-30°C during the day and above 15°C at night. It can tolerate some cold temperatures, but frost can damage the leaves and reduce its growth.
Soil: The plant requires well-draining soil that is neutral to slightly acidic (pH range of 6.0-7.5). Soil with high organic matter content is also important for healthy growth. The preferred soil texture is sandy to loamy soil, although it can also grow in clay soil with good drainage. It is a robust plant that can tolerate some soil salinity and can grow in soils with low fertility.
Cultivation Methods
Digitaria gayana is a warm season grass that thrives in tropical and subtropical regions. The grass does best in well-drained, fertile soils that are rich in organic matter and have a pH between 6.0 and 7.5. The grass can be propagated by seeds, but it is recommended to propagate by vegetative means since the first cut of the seed-grown grass results in reduced yields.
Watering Needs
Digitaria gayana requires regular watering, especially during dry periods. The grass needs about 25-30mm of water every week. However, avoid overwatering, as it can lead to root rot. An effective method of watering is by drip irrigation, which ensures that water is supplied directly to the roots, minimizing water loss through evaporation.
Fertilization
Digitaria gayana requires a lot of nitrogen for optimal growth, and it will benefit from regular applications of nitrogen fertilizers. A recommended fertilizer application is 200-300kg/ha of nitrogen per year. Phosphorus and potassium are also essential for growth, and their application rates should be adjusted based on the soil test results.
Pruning
Digitaria gayana can grow up to two meters tall if left unpruned. However, for optimal yields, it is recommended to prune the grass to a height of between 10-15cm. Regular pruning also promotes tillering and increases the leaf to stem ratio, leading to better quality grass. Pruning should be done when the grass is in its vegetative stage and avoid pruning during the flowering stage since it can reduce the yield.
Propagation of Digitaria gayana (Kunth) A.Chev. ex Stapf
Digitaria gayana (Kunth) A.Chev. ex Stapf is usually propagated by vegetative means, primarily through stem cuttings or seed sowing.
Propagation by Stem Cuttings
The propagation of Digitaria gayana by stem cuttings involves the selection of suitable plant material, usually with a minimum of two nodes. The cuttings are taken from mature plants and are propagated under suitable environmental conditions and soil moisture levels. The cuttings can be propagated in the soil, in planting trays, or in other suitable growing media. The cuttings usually root within two weeks, and they should be watered regularly until they are well established.
Propagation by Seed Sowing
Digitaria gayana is propagated by seed sowing, which can be done indoors or outdoors. The seeds should be sown in a prepared seedbed or directly in the field. The planting depth should be no more than 1 cm, and the seeds should be spaced at a distance of 10-15 cm, depending on the growth habits and density of the plant. The seeds usually germinate within one to two weeks, and the seedlings should be watered regularly until they are well established.
Disease Management
Digitaria gayana is susceptible to several diseases, including Anthracnose, Rust, and Leaf Spot. These diseases can affect the growth and yield of the plant. It is important to identify the disease at an early stage to manage and control it effectively. The following are some management strategies:
- Use clean planting materials to avoid introducing the disease to the field.
- Practice crop rotation to reduce the build-up of the pathogen in the soil.
- Spray fungicides on the plant to control the spread of the disease.
- Monitor the plant regularly to catch the disease at an early stage and to prevent it from spreading.
Pest Management
Digitaria gayana is also susceptible to several pests, including grasshoppers, cutworms, armyworms, and mites. These pests can cause significant damage to the plant, leading to a reduction in yield. The following are some management strategies:
- Use insecticides to control the population of pests on the plant.
- Practice crop rotation to prevent the buildup of pests in the soil.
- Use pheromone traps to monitor the population of pests and to catch them at an early stage.
- Remove weeds from the field to reduce the hiding places of pests and their potential hosts.
It is important to note that the use of pesticides should be done with caution to avoid harmful effects on beneficial organisms, the environment, and human health. It is advisable to seek professional advice before using any chemical control measures.
