Overview
Rhynchosia viscosa (Roth) DC. subsp. violacea (Hiern) Verdc. is a species of flowering plant in the family Fabaceae. Commonly known as purple butterfly-pea or sticky snoutbean, this plant is widely distributed in tropical Africa, from Senegal to Sudan, Kenya, and Tanzania. It is valued for its medicinal properties and ornamental value.
Description
Rhynchosia viscosa subsp. violacea is a perennial herb that can grow up to 60 cm in height. Its stems are erect or ascending and are covered with numerous short, glandular hairs that give them a sticky appearance. The leaves are trifoliate, with each leaflet ovate or elliptical in shape. The upper surface of the leaves is covered with short hairs, while the lower surface is densely covered with longer, glandular hairs.
The flowers of Rhynchosia viscosa subsp. violacea are purple or violet in color, with a standard petal that is typically 1.5 cm long and hairy at its base. The fruit is a legume that is flattened, hairy, and up to 3 cm long.
Uses
Rhynchosia viscosa subsp. violacea has a variety of medicinal uses. In traditional African medicine, the plant is used to treat a range of ailments, including menstrual disorders, fever, and snakebites. The roots of the plant are also used as a purgative and to treat digestive problems. In addition, the plant is believed to have astringent and anti-inflammatory properties.
Aside from its medicinal benefits, Rhynchosia viscosa subsp. violacea is also used for ornamental purposes. Its attractive purple flowers make it a popular choice for gardens and landscaping.
Cultivation
Rhynchosia viscosa subsp. violacea is a hardy plant that is easy to grow. It prefers well-draining soil and should be watered regularly. The plant can be propagated from seeds or cuttings and should be planted in full sun or partial shade. In areas with colder climates, the plant may need to be protected from frost.
Light Requirements
The plant Rhynchosia viscosa (Roth) DC. subsp. violacea (Hiern) Verdc. grows best in full sun or partial shade. It can tolerate some shade, but too much shade will reduce its growth. Adequate sunlight will ensure that the plant develops strong stems and leaves.
Temperature Requirements
The plant Rhynchosia viscosa (Roth) DC. subsp. violacea (Hiern) Verdc. thrives in warm temperatures. The ideal temperature range is between 25°C to 35°C (77°F to 95°F). Temperatures below 10°C (50°F) can be detrimental to the growth of the plant. In cold climates, this plant should be grown in a greenhouse or indoors.
Soil Requirements
This plant can grow in a wide range of soils, but it prefers well-drained soil that is rich in organic matter. The soil should have a pH between 6.0 and 7.5. The plant can tolerate some salinity, but it does not do well in waterlogged soils. It is recommended to add compost or aged manure to the soil to improve its fertility.
Cultivation Methods for Rhynchosia viscosa (Roth) DC. subsp. violacea (Hiern) Verdc.
Rhynchosia viscosa (Roth) DC. subsp. violacea (Hiern) Verdc. is a plant that grows well in well-draining soil with a pH of 6.5-7.5. The plant prefers sandy loam soil and is tolerant of short periods of flooding. The plant should be grown in full sun, as it requires at least 6 hours of sunlight per day to thrive.
If you are growing Rhynchosia viscosa (Roth) DC. subsp. violacea (Hiern) Verdc. from seeds, it is recommended that you sow the seeds in a seedbed and transplant the seedlings after 3-4 weeks. Alternatively, the plant can also be propagated through stem cuttings with at least two nodes. The cuttings should be planted in warm soil and kept moist until they have established roots.
Watering Needs
Rhynchosia viscosa (Roth) DC. subsp. violacea (Hiern) Verdc. requires moderate watering. It is recommended that the plant is watered once a week, depending on rainfall. The soil should be kept moist, but not waterlogged. Overwatering could lead to root rot and other fungal diseases. However, it is important to make sure the plant receives enough water during its initial growth stage.
Fertilization
Rhynchosia viscosa (Roth) DC. subsp. violacea (Hiern) Verdc. benefits from occasional fertilization to promote healthy growth. An all-purpose fertilizer can be applied during the growing season to enhance the plant's vigor. It is recommended that you use a slow-release fertilizer as it will provide nutrients over a longer period of time.
Pruning
Pruning is not necessary for Rhynchosia viscosa (Roth) DC. subsp. violacea (Hiern) Verdc. However, if the plant becomes too dense, it can be pruned to promote better airflow and sunlight penetration. Additionally, you may trim back any dead, diseased, or damaged branches to maintain the plant's overall health.
Propagation of Rhynchosia viscosa subsp. violacea
Rhynchosia viscosa subsp. violacea can be propagated through both seeds and stem cuttings.
Propagation via Seeds
Seeds of Rhynchosia viscosa subsp. violacea can be collected from mature pods. The seeds should be sown in a well-drained seed-raising mix in a suitable pot or seedling tray. The seeds should be placed just below the soil surface and kept moist. Germination should occur within several days to a couple of weeks. After germination, the seedlings can be gradually introduced to more sunlight and less water, until they are ready for planting in their permanent location.
Propagation via Stem Cuttings
Stem cuttings of Rhynchosia viscosa subsp. violacea can be taken from healthy plants. Cuttings should be taken from semi-hardwood stems and should be around 10 cm long. All leaves should be removed from the lower half of the cutting and any flowers or buds should also be removed. The cuttings should be dipped in a rooting hormone before being planted in a well-drained potting mix. The mix should be kept moist, and the cuttings should be kept in a warm, shaded area until they show signs of new growth. Once new growth appears, the cuttings can be gradually introduced to more sunlight, and can be transplanted to their permanent location once they have established roots.
Disease and Pest Management for Rhynchosia Viscosa subsp. Violacea
Rhynchosia viscosa subsp. violacea, commonly known as Purple snout bean, is generally a hardy and disease-resistant plant. However, several pests and diseases can still infect the plant and cause destruction. Here are some common diseases and pests of the plant and how to manage them effectively:
Diseases
Fungal diseases:
Fungal infections are rampant in plants, and Rhynchosia viscosa subsp. violacea is not immune to it. The plant can be infected with various fungi, including powdery mildew, leaf spot, and rust.
To manage fungal diseases, removing the infected parts of the plant and increasing airflow around the plant can be helpful. Also, using fungicides specifically for the disease can stop its spread. However, it is best to consult with a professional before administering any fungicide.
Viral diseases:
Viral infections are challenging to deal with because viruses are not single-celled organisms. Instead, they use the host plant's cells to replicate themselves, causing a wide range of effects, including stunted growth, yellowing, and death.
Since there are no known organic or chemical management practices for viral infections, it is best to remove and destroy infected plants to prevent the spread of the virus further.
Pests
Aphids:
Aphids are tiny insects that suck sap from the plant, causing the leaves to yellow and stunt growth. They can also transmit viruses to the plant.
To get rid of aphids, use insecticides or beneficial insects such as ladybugs to control their population.
Leaf miners:
The leaf miner larvae tunnel through leaves, causing the leaves to dry and eventually fall off.
To manage leaf miners, remove infected foliage, encourage natural enemies of leaf miners, and apply pheromone traps to attract and capture the adult leaf miner.
Caterpillars:
Caterpillars, such as the bean pod borer, are a common pest of the Rhynchosia viscosa subsp. violacea plant. They feed on the plant's leaves and pods, causing extensive damage.
To manage caterpillar infestation, handpick the caterpillars and destroy them manually, use biological pesticides, or spray the plant with chemical insecticides carefully.
In conclusion, managing pests and diseases in Rhynchosia viscosa subsp. violacea involves identifying the problem, selecting an appropriate management strategy, and closely monitoring the plant to ensure the pest or disease does not return.
