Origin
Sphenostylis schweinfurthii Harms subsp. schweinfurthii, also known as the African Yam Bean, is a crop that is native to tropical Africa and has been grown there for over 2000 years. It is widely grown in West and Central Africa, especially in Nigeria and Cameroon. This leguminous plant prefers soils that are well-drained and rich in organic matter. The plant is adapted to grow in a range of agro-ecologies, from semi-arid to sub-humid regions.
Common Names
The African Yam Bean is known by a range of names including:
- Ewa
- Akidi
- Agwa
- Kamande
- Nefi
- Nzama
- Onyipa
- Sese
Uses
The African Yam Bean is an important source of protein, carbohydrates, and minerals for millions of people in Africa. Its beans are used in a variety of ways, including boiling, steaming, frying, and roasting. The beans can also be ground into flour, which can be used to make cakes, bread, and porridge. In addition, the plant can be used as animal feed, and its leaves and stems are used as leafy vegetables.
General Appearance
The African Yam Bean is a perennial plant that can grow up to 2 meters tall. It has a deep taproot system and its stems are woody and have a reddish-brown color. The leaves of the plant are trifoliate and are purple or green in color. The flowers are pinkish-purple and are borne on long racemes. The pods of the plant are 10-20cm long and contain between 2-5 seeds per pod. The seeds are small, white, and kidney-shaped.
Light Requirements
Sphenostylis schweinfurthii Harms subsp. schweinfurthii is a plant species that prefers to grow in full sunlight. The plant necessitates access to direct sunlight for a good part of the day to grow healthily.
Temperature Requirements
The plant usually prefers warmer temperatures, and it can grow in warmer areas than the vast majority of bean plants, with optimum growth occurring in temperatures ranging from 20°C to 30°C. The subspecies can sustain itself in temperatures as low as 18°C and as high as 35°C, but growth and development slow down when exposed to temperatures beyond these ranges.
Soil Requirements
The subspecies Sphenostylis schweinfurthii Harms subsp. schweinfurthii grows healthiest in well-drained soils with neutral to mildly acidic pH levels. It can, nonetheless, grow in slightly alkaline soils. It is important to note that the plant does not thrive in poorly-drained and waterlogged soils, which can lead to root rot and other diseases.
Cultivation
Sphenostylis schweinfurthii Harms subsp. schweinfurthii is a tropical legume that is easy to cultivate in warm climates. It does best in well-draining soil with a neutral pH, although it can tolerate slightly acidic or alkaline soils.
This plant prefers a sunny location, but it can also grow in partial shade. It's best to avoid areas that have strong winds or are prone to flooding, as this can damage the plant.
Watering Needs
Sphenostylis schweinfurthii requires regular watering during the growing season, but it doesn't like to have its roots sitting in water. Water it deeply once a week, or more often if the soil is dry. Reduce the watering frequency during periods of rain or cooler temperatures.
Fertilization
It's useful to apply a balanced fertilizer at the beginning of the growing season to promote healthy growth. This legume plant is known for fixing nitrogen, so it doesn't require excessive fertilization. However, if the leaves start to yellow, then that may mean it needs a nitrogen supplement.
Pruning
The pruning of Sphenostylis schweinfurthii is relatively simple. Remove any aged or diseased stems just before the growing season starts, which aids in new growth. You can also prune it in the fall after seed formation, cutting down the entire plant to the root, but this is optional.
Propagation of Sphenostylis Schweinfurthii Harms subsp. Schweinfurthii
Sphenostylis schweinfurthii Harms subsp. schweinfurthii, commonly known as African Yam Bean, is a hardy perennial herb that belongs to the family Fabaceae. The plant is native to the tropical regions of Africa and is increasingly gaining popularity in other parts of the world, including Asia and South America. Propagation of Sphenostylis schweinfurthii Harms subsp. schweinfurthii can be done through different methods, including:
Seed Propagation
The most common method of propagating Sphenostylis schweinfurthii Harms subsp. schweinfurthii is through the use of seeds. The seeds of the plant are readily available in local nurseries, seed banks, or through online stores. Seed propagation requires that the seeds be soaked in lukewarm water for several hours to help soften their coats and hasten germination. The seeds should then be sown in a well-draining potting mix, watered, and placed in a warm, humid location. Germination of the seeds may take several weeks, and after the emergence of seedlings, they should be carefully transplanted to their permanent position.
Cuttings Propagation
Propagation of Sphenostylis schweinfurthii Harms subsp. schweinfurthii may also be done through the use of cuttings. This method is best suited for plants that have strong, mature stems. To propagate through cuttings, take a section of stem measuring about 8-10 inches, remove the leaves from the bottom two-thirds of the cutting, and then dip the cut end into rooting hormone powder. The prepared cutting should then be planted in a potting mix of peat and sand, watered gently, and placed in a warm, humid location. The rooted cuttings should be transplanted into their permanent position after they have developed a strong root system.
Division
Propagation of Sphenostylis schweinfurthii Harms subsp. schweinfurthii can also be done through division. This method is best suited for mature plants that have large clumps of roots. To propagate through division, carefully dig up the plant and gently separate the clumps of roots into individual plants. Each new plant should have several stems and a healthy root system. These new plants should be planted in their permanent position as soon as possible and watered well.
In conclusion, Sphenostylis schweinfurthii Harms subsp. schweinfurthii can be propagated through different methods, including seed propagation, cuttings propagation, and division. Care should be taken to provide a warm and humid environment for the newly propagated plants, and they should be transplanted to their permanent position as soon as they have developed a strong root system.
Disease and Pest Management for Sphenostylis schweinfurthii Harms subsp. schweinfurthii
Sphenostylis schweinfurthii Harms subsp. schweinfurthii is susceptible to several diseases and pests that may affect its growth and yield. An essential aspect of managing such diseases and pests is to maintain crop hygiene by removing all infected plant material regularly. It is also necessary to use clean seed and proper planting materials to raise healthy crops.
Common Diseases
The most common diseases that affect Sphenostylis schweinfurthii Harms subsp. schweinfurthii include:
- Anthracnose: This is a fungal disease that causes irregular or circular sunken lesions on the leaves, stems, and pods of the plant. In severe cases, the plant may experience defoliation and death. To manage anthracnose, planting resistant varieties, removing infected plant material, and applying fungicides can be useful.
- Root Rot: Root rot is caused by a water mold that affects the roots and causes them to rot. Symptoms of the disease include yellowing leaves, wilting, stunting, and eventual death of the plant. To manage root rot, avoid planting in waterlogged or poorly drained soils, and using fungicides. Maintaining proper soil drainage is also crucial.
- Leaf Spot: Leaf spot is a fungal disease that causes small, round, brown spots on the leaves that gradually progress to larger and angular spots. The spots may turn yellow or tan with a reddish-brown margin. To manage leaf spot, remove infected plant material, increase air circulation around the plants, and apply fungicides.
Common Pests
The common pests that affect Sphenostylis schweinfurthii Harms subsp. schweinfurthii include:
- Aphids: Aphids are small, pear-shaped insects that suck the sap from the leaves and stems of the plant. This can lead to stunted growth and distortion of the leaves. To control them, use insecticidal soaps or natural predators such as ladybugs and lacewings.
- Mites: Spider mites are tiny and cause white or yellowish spots on leaves, which later turn brown. These pests are prevalent during warm and dry weather conditions. To control them, increase humidity around the plants, use predatory mites, and spray insecticidal soap.
- Whiteflies: Whiteflies are tiny, winged insects that suck sap and secrete honeydew, leading to the development of black sooty mold. This can cause stunted growth and lead to plant death. To control them, increase air circulation around the plants, use insecticidal soap, and sticky traps.
It is crucial to monitor the plants regularly to identify and manage any diseases and pests that may affect them. A combination of cultural, physical, mechanical, and chemical methods of management can help achieve better crop yields.
