Origin
Digitaria debilis (Desf.) Willd. belongs to the family Poaceae and is believed to have originated in South America.
Common Names
The plant is commonly known as weak finger grass or tropical crabgrass. In some regions, it is also referred to as summer grass or small crabgrass.
Uses
Digitaria debilis serves various purposes, including soil stabilization, animal feed, and ornamental purposes. The plant's roots help reduce soil erosion, making it valuable in controlling soil loss. Additionally, the plant is a great source of forage for livestock, especially during the dry season. The plant is also used for ornamental purposes in landscaping and lawn care, where it is grown as a decorative grass.
General Appearance
Digitaria debilis is a small, annual grass with a height ranging from 20 to 60 cm. The plant's leaves are narrow, about 2 to 7 mm wide, and have a characteristic green color. The flowers of Digitaria debilis are arranged in compacted spikes, making it easy to differentiate from other grasses. The plant has small seeds that are typically brown or yellow in color and are about 1 to 2 mm long.
Light Conditions
Digitaria debilis prefers full sunlight, where it can receive at least 6 to 8 hours of direct sunlight per day. It can tolerate partial shade, but the growth rate may be slower.
Temperature Requirements
The optimal temperature range for the growth of Digitaria debilis is between 20°C to 35°C. However, it can tolerate temperature extremes ranging from -5°C to 45°C. The plant grows well in tropical and subtropical regions.
Soil Requirements
Digitaria debilis can grow in a wide range of soil types. However, it prefers well-drained soils, with a pH range between 5.5 and 7.5. Soil should be rich in organic matter and have good water-holding capacity. The plant can tolerate drought conditions, but excessive moisture can lead to root rot disease.
Cultivation Methods
The Digitaria debilis (Desf.) Willd. plant can be easily grown through its seeds. The best time to plant the seeds is in the spring or summer when the weather is warm. It is crucial to ensure that the soil in which the seeds are planted is well-draining and fertile, with a pH of about 6.5-7.
Watering Needs
The Digitarria debilis (Desf.) Willd. plant requires moderate watering. It is important to ensure that the plant is watered once a week. When watering, the soil should be watered generously such that it is evenly moist, but do not overwater, as this can cause root rot and other diseases.
Fertilization
The Digitaria debilis (Desf.) Willd. plant requires regular fertilization to thrive. Fertilizers rich in nitrogen, phosphorus, and potassium are suitable for this plant. It is recommended to fertilize the plant about once every month during the growing season. Avoid overfertilizing as this can cause burns on the plant leaves and damage to the roots.
Pruning
Digitaria debilis (Desf.) Willd. plant requires regular pruning to maintain its shape and look neat. Pruning helps to promote growth and shape the plant. It is recommended to prune the plant once every 6-8 weeks during the growing season. Remove any dead or damaged leaves and stems. Use sterilized pruning equipment to avoid spreading diseases to the plant.
Propagation of Digitaria debilis
Digitaria debilis (Desf.) Willd. is propagated through seeds and vegetative propagation methods, such as stem cuttings and division of the root mass.
Seed Propagation
Seeds of Digitaria debilis are collected from the mature plants during the fall season. The collected seeds are then dried, cleaned and stored in a cool and dry place. The seeds are sown in the early spring season in a well-draining soil mixture. The soil should be kept moist, but not soggy. Germination usually takes place within two to three weeks, and the seedlings can be transplanted to individual pots after the development of the second set of leaves.
Vegetative Propagation
Stem cuttings and root division are two vegetative propagation methods used for Digitaria debilis. For stem cuttings, take a 3-4 inch long cutting of the plant's stem, including a few leaves. Dip the cutting in rooting hormone powder and plant it in a well-draining soil mixture. The soil should be kept moist, and roots should start developing in two to three weeks. After the roots are well-developed, the new plant can be transplanted to a larger container or planted in the ground.
For root division, the mature plant's root mass is carefully lifted from the soil. The root mass is divided into smaller sections, ensuring that each section has a sufficient number of roots and shoots. These divided sections are planted in individual pots or directly in the garden bed. The soil should be kept moist, and the plants should be protected from direct sunlight until they are well-established.
Disease Management
Digitaria debilis is susceptible to several foliar and stem diseases including anthracnose, leaf spots, and rust diseases. These diseases result in black, brown, or red spots on the leaves, wilting, and in severe cases death of the plant. The following management practices can help control these diseases:
- Rotate crops to reduce the buildup of disease-causing organisms in the soil.
- Remove and destroy infected plant residues to prevent the spread of disease.
- Avoid overhead irrigation to reduce leaf wetness and minimize the risk of infection.
- Apply fungicides during early stages of infection to prevent the spread of the disease.
Pest Management
Digitaria debilis is also prone to attacks by several pests, including grasshoppers, aphids, and cutworms. These pests can cause physical damage to the plants, reduce their productivity, and eventually lead to the death of the affected plant. The following management practices can help reduce the impact of these pests:
- Use insect-resistant varieties of the plant.
- Monitor the growth of the plant regularly to detect early signs of pest infestation.
- Use insecticides as a control measure in case of a severe pest infestation.
- Use cultural control measures such as trapping and handpicking to manage pest populations naturally.
