Origin and Common Names
Dilophotriche tuberculata (Stapf) Jacq.-Fél., commonly known as the "yellow torch" or "golden torch," is a herbaceous perennial plant native to the highlands of eastern Africa, mainly in Ethiopia and Kenya.
Description
The plant's leaves are arranged in a basal rosette and are linear in shape, growing up to 12 inches long. The stems are tall and erect, reaching up to six feet in height, and are topped with a dense spike of bright yellow flowers that resemble a torch.
The flowering period occurs between August and November, and the flowers attract several pollinators such as bees, butterflies, and birds. The seeds are small and black, and the plant spreads by underground rhizomes.
Uses
In Ethiopia, the plant is used in traditional medicine to treat various ailments like fever, cough, and inflammation. The roots and leaves are infused in water or chewed to make decoctions or poultices. Dilophotriche tuberculata is also popular in horticulture as an ornamental plant, mainly in rock gardens, borders, and containers due to its attractive appearance and drought tolerance.
Moreover, the plant has ecological importance as it helps in soil erosion control and is an essential food source for herbivores like dik-diks and gazelles. The plant is being threatened by habitat loss due to agriculture, deforestation, and land-use changes.
Light Requirements
Dilophotriche tuberculata requires moderate to full sunlight, with a preference for filtered light in hotter climates. The plant can adapt to both direct and indirect light sources and grows well in partially shaded areas.
Temperature Requirements
This plant species thrives in warm temperatures and requires temperatures between 20°C to 30°C for proper growth and development. Dilophotriche tuberculata can also withstand short periods of cool weather and light frost, but prolonged exposure to extreme temperatures can inhibit growth and damage the plant.
Soil Requirements
Dilophotriche tuberculata prefers well-draining soil that is rich in nutrients. The ideal soil pH for this plant species ranges from 6.0 to 7.5. In their natural habitat, these plants are found growing in sandy soils that are slightly acidic, but they can also grow well in loamy or clay soils with proper fertilization.
Cultivation and Care of Dilophotriche tuberculata
Dilophotriche tuberculata is a hardy evergreen shrub that can be grown outdoors in subtropical and warm temperate regions.
Planting and Soil Requirements
The plant prefers well-draining soil that is rich in organic matter. It needs a full to partial sun exposure and requires a warm, sheltered location that is protected from wind. It is recommended to plant the shrub in early spring, allowing it enough time to establish before winter.
Watering Needs
Dilophotriche tuberculata is tolerant of drought, but regular watering is needed for the plant to grow healthy and thrive. Water the plant deeply once a week in the growing season and reduce watering in winter.
Fertilization
Regular fertilization is required for the plant to produce lush foliage and flowers. Fertilize the shrub with a slow-release fertilizer in early spring and once again in mid-summer.
Pruning
Prune the plant in late winter or early spring to remove diseased or damaged branches and encourage new growth. Cutting back one-quarter to one-third of the height of the plant will also promote bushier growth and increase flowering.
With proper care, Dilophotriche tuberculata can be a striking addition to any garden or landscape.
Propagation of Dilophotriche tuberculata
Dilophotriche tuberculata is a semi-succulent plant that belongs to the family Asteraceae. It is a native plant of South Africa and grows well in tropical and subtropical regions. The plant can be propagated through multiple methods, including:
Seeds Propagation
Seeds are the most common method for propagating Dilophotriche tuberculata. The seeds are small and can be collected from mature plant flowers or purchased from plant nurseries. For best results, sow the seeds in a well-drained potting mix that is kept moist. Germination typically occurs within 2-4 weeks when the seeds are kept at temperatures around 20-25°C.
Stem Cuttings Propagation
Stem cuttings are another method for propagating Dilophotriche tuberculata. Take cuttings from mature plants early in the growing season with a sterilized blade. Remove the bottom leaves, dip the cut ends in rooting hormone, and place the cuttings in well-draining soil mix. Water the cutting sparingly, and keep it in a humid environment under indirect light. After rooting, repot the cutting to encourage further growth.
Division Propagation
Dilophotriche tuberculata can also be propagated through division. Mature plants can be carefully divided into smaller sections with a sterilized blade or digging tool. Each section should contain some roots and shoots. Plant the divisions in a well-draining soil mix and water sparingly until new growth appears.
Disease Management
Dilophotriche tuberculata, commonly known as sun hemp, is generally resistant to diseases, and no specific diseases have been observed to affect the plant. However, some fungi such as Fusarium oxysporum, Rhizoctonia spp., and Sclerotium rolfsii can cause root rots and wilting in the plant. The best measures to manage such diseases include:
- Planting disease-free seeds or seedlings
- Avoiding overwatering or waterlogging on the field
- Practicing crop rotation with non-host crops to prevent soil-borne diseases
- Applying fungicides such as carbendazim, thiophanate-methyl, and metalaxyl in case of severe outbreaks
Pest Management
Various pests can affect Dilophotriche tuberculata. Some of the common pests include:
- Leaf-eating caterpillars such as Spodoptera litura, Heliothis armigera, and Prodenia litura
- Pod borer such as Maruca vitrata
- Aphids such as Aphis gossypii
- Spider mites such as Tetranychus neocaledonicus and Tetranychus urticae
- Root-knot nematode such as Meloidogyne spp.
The following are the ways to control these pests:
- Using pheromone traps or light traps to monitor and control the population of moths and caterpillars
- Avoiding excess use of nitrogenous fertilizers to minimize infestation by aphids
- Applying insecticides such as spinosad, emamectin benzoate, and lambda-cyhalothrin to control the pests
- Using botanical pesticides such as neem oil and pyrethrum extracts to repel the pests
