Origin
Macrolobium coeruleum (Taub.) Harms belongs to the family Fabaceae and is native to tropical Africa, primarily found in forests and savannahs.
Common Names
The plant is commonly known as Blue Bean Tree, Blue Mango, and Jengkol. It is also called the Marela or Marela Kina in some African dialects.
Uses
The seeds of Macrolobium coeruleum are edible and are consumed in some African countries, including Cameroon, Congo, and Gabon. They are a rich source of protein and are sometimes roasted and eaten as a snack. The wood of the Blue Bean Tree is strong and durable, and is used for making furniture, construction, and fuel. The plant also has medicinal properties and is used in traditional African medicine to treat various ailments, including digestive issues, respiratory infections, and infertility.
General Appearance
The Blue Bean Tree is a medium-sized tree that can grow up to 30 meters tall. Its bark is smooth and grayish-brown in color, and its leaves are compound with five to seven leaflets. The flowers of the plant are small, yellowish-green, and are produced in dense clusters. The fruit of the plant is a large pod that is initially green before turning brownish-black when mature. Each pod contains several seeds, which are oval-shaped, flat, and dark brown in color.
Light Requirements
Macrolobium coeruleum prefers full sunlight to partial shade for optimal growth and development. It can tolerate some shade but excessive shade can lead to poor growth and flowering.
Temperature Requirements
The ideal temperature range for the growth of Macrolobium coeruleum is between 20°C and 30°C. It can tolerate slightly lower temperatures but is sensitive to frost. Extreme temperatures can lead to stunted growth, leaf loss, and even death of the plant.
Soil Requirements
The plant thrives in well-drained soils that are rich in nutrients. It can grow in a wide range of soil types including sandy, loamy, and clay soils. However, it is sensitive to waterlogged soils and requires good drainage to avoid waterlogging. Soil pH should be slightly acidic to neutral (pH 5.5-7.0) for optimal growth.
Cultivation of Macrolobium coeruleum
Macrolobium coeruleum (Taub.) Harms is a fast-growing, low maintenance plant that can thrive in both tropical and subtropical climates. It can be grown outdoors in gardens or indoors as a houseplant.
The plant prefers well-draining soil that is nutrient-rich and slightly acidic. It also requires partial to full sunlight exposure for optimal growth.
Watering needs
Macrolobium coeruleum requires moderate watering. It should be watered when the soil is completely dry to the touch, but avoid overwatering as it can lead to root rot. During the dry season, the plant may require more frequent watering to prevent plant dehydration.
Fertilization
Fertilization is essential for the proper growth and development of Macrolobium coeruleum. The plant benefits from a balanced fertilizer application every three months during the growing season. Use a slow-release granular fertilizer and follow the manufacturer's instructions for the application rate.
Pruning
Pruning of Macrolobium coeruleum involves the removal of damaged, diseased, or dead branches. Trimming also promotes the growth of new healthy branches and maintains the plant's shape. Pruning should be done during the growing season to avoid damage to the plant.
It is also important to note that the plant may require staking as it grows to provide support for the stems.
Propagation of Macrolobium coeruleum (Taub.) Harms
Macrolobium coeruleum (Taub.) Harms, commonly known as Butterfly Tree, is propagated using various methods that include:
Seed Propagation
The propagation of Macrolobium coeruleum through seeds is commonly used to produce new plants. Seeds are collected during the fruiting season, which is usually between October and December. The seeds are first washed with clean water to remove any debris. They are then soaked in water for 24 hours to soften the seed coat and promote germination. The seeds are sown in a well-draining medium and kept moist. Germination usually occurs within 21-28 days.
Cuttings
Cuttings from healthy, mature Macrolobium coeruleum plants can be used to propagate new plants. The cuttings should be taken during the vegetative growth stage, which is usually in early spring. The cuttings should be about 15-20cm long and should be taken from the tips of the branches. The leaves should be removed from the lower half of the cutting, and the stem should be treated with rooting hormone. The cuttings can then be planted in a well-draining medium and kept moist. Rooting occurs within 3-4 weeks.
Division
Division is another propagation method that is used for Macrolobium coeruleum. The plant is dug up and divided into smaller sections using a sharp, sterile knife. Each division should contain several stems and a good root system. The divisions are then planted in a well-draining medium and watered well. They should be kept moist until they are established, which usually takes about 3-4 weeks.
Air Layering
Air layering is a propagation method that is commonly used for Macrolobium coeruleum. The stem of the parent plant is wounded by removing a ring of bark. The wound is then treated with rooting hormone and covered with moist sphagnum moss. The moss is then wrapped with plastic to keep it moist and secure. The roots will form at the wound site, and once they are well established, the stem can be cut from the parent plant and planted in a well-draining medium.
Propagation of Macrolobium coeruleum is relatively easy, and new plants can be produced using any of the above methods.
Disease and Pest Management for Macrolobium coeruleum (Taub.) Harms
Macrolobium coeruleum (Taub.) Harms is a plant species that is native to the tropical regions of Central and South America. This species is highly valued for its ornamental value, and it is also used as a source of timber, charcoal, and agricultural land. However, Macrolobium coeruleum (Taub.) Harms is vulnerable to a variety of diseases and pests that can cause adverse effects on its growth and survival.
Common Diseases
One of the most common diseases that affect Macrolobium coeruleum (Taub.) Harms is root rot. This disease is caused by various soil-borne fungi that invade the roots and cause decay. Symptoms of root rot include stunted growth, yellowing of leaves, and wilting of foliage. To manage this disease, it is essential to avoid waterlogging and ensure proper drainage of the soil. The use of fungicides may also be necessary.
Another disease that can affect Macrolobium coeruleum (Taub.) Harms is leaf spot. This disease is caused by fungi or bacteria and can lead to the formation of circular or irregular spots on leaves. These spots may appear brown, black, or yellow. To manage leaf spot, it is necessary to remove infected leaves and promote proper air circulation to avoid creating a humid environment.
Common Pests
The most common pests that attack Macrolobium coeruleum (Taub.) Harms are aphids and mites. Aphids are small, soft-bodied insects that tend to cluster on the underside of leaves. They suck the sap of the plant, causing stunted growth, distortion of foliage, and yellowing of leaves. To manage aphids, it is necessary to remove them physically or use insecticides. Mites, on the other hand, are tiny arachnids that cause wilting and discoloration. To manage mites, it is necessary to use insecticides and avoid creating a hot and dry environment.
Caterpillars are also common pests that can affect Macrolobium coeruleum (Taub.) Harms. These insects feed on the foliage, causing holes and defoliation. To manage caterpillars, it is necessary to remove them physically, use insecticides or introduce natural predators such as birds or beneficial insects.
Overall, disease and pest management for Macrolobium coeruleum (Taub.) Harms requires a combination of preventive and corrective measures. A healthy plant that grows in the right conditions is less likely to suffer from diseases and pests, but when they are present, swift action is crucial to minimize damage and prevent spread.
