Overview of Psorospermum laxiflorum (Engl.) Engl.
Psorospermum laxiflorum (Engl.) Engl., also known as African sandalwood, is a tropical tree belonging to the family Clusiaceae. The plant is native to West and Central Africa, particularly in Cameroon, Congo, and Gabon.
Common Names
The plant is known by different common names in its native regions. In Cameroon, it is called "Mbol," while in Gabon, it is referred to as "Ongo." In Congo, it is known as "Mitaban alatolisi."
Uses
Psorospermum laxiflorum is popular for its medicinal properties. The plant's bark, roots, and leaves are essential in traditional medicine to treat various health conditions such as skin diseases, rheumatism, and fever. The bark is used to create a decoction that is used for blood purification and also for the treatment of liver ailments, and typhoid fever. The plant also contains antimicrobial, antifungal, and anti-inflammatory properties.
The African sandalwood tree is also valued for its timber. Its wood is durable and resistant to termites, and it is commonly used for building construction and furniture making. In addition, the tree's essential oils are extracted from the bark, and they possess scent properties similar to sandalwood, hence its common name.
General Appearance
Psorospermum laxiflorum is a medium-sized tree that grows up to 20 meters in height. Its bark is grayish-brown, and it has a slightly fissured texture. The leaves are simple, alternate, and ovate, with a length of about 10-15 cm. The flowers of the African sandalwood tree are yellow and have a diameter of about 10 cm, while its fruits are capsules that contain three or four large seeds.
Growth Conditions for Psorospermum Laxiflorum
Light: Psorospermum Laxiflorum grows in partial sun to partial shade. It does not do well in full sun conditions. Be sure to place the plant in an area that gets plenty of light, but avoid direct sunlight for extended periods of time.
Temperature: This species prefers warm temperatures throughout the year. It requires a minimum temperature of 60°F (15.5°C) and a maximum temperature of 85°F (29.4°C). So, it can do well in most climates, as long as the temperature range is within these limits. It is important to note that this plant cannot tolerate frost or extremely cold temperatures.
Soil: The plant prefers well-drained, moist soil that is rich in organic matter. A pH level of 6.0 to 7.5 is ideal for its growth. Additionally, it requires nutrient-rich soil with a good balance of nitrogen, phosphorus, and potassium. Psorospermum Laxiflorum can also benefit from occasional fertilization during the growing season.
Water: The plant requires moderate watering, and it is not drought-tolerant. Water the plant thoroughly and allow the soil to dry out slightly before the next watering. During the winter, reduce the watering frequency to avoid water-logging the plant.
Humidity: Psorospermum Laxiflorum prefers moderate to high humidity levels. If the air is too dry, the plant may suffer from leaf drop, browning leaves, and other issues. Mist the plant regularly or place a humidifier nearby to increase the humidity levels.
Propagation: Propagation of Psorospermum Laxiflorum can be done by stem cuttings, layering, or by seed propagation. If done properly, propagation by stem cuttings and layering can produce a much faster-growing plant than by seed propagation.
Cultivation Methods for Psorospermum Laxiflorum
Psorospermum laxiflorum is a tropical plant commonly found in the rainforest. It thrives in warm and humid conditions, so it needs to be grown in a warm environment. The plant prefers well-draining soil that is slightly acidic and regularly fertilized. It can be propagated by stem cuttings, seeds or air layering.
Watering Needs for Psorospermum Laxiflorum
Watering Psorospermum laxiflorum is an essential aspect of its care. The plant requires constant moisture in its soil, but overwatering can lead to root rot. The watering frequency depends on environmental factors such as temperature, humidity, and soil type. You should avoid letting the soil dry out completely. During the dry season, the plant may need more frequent watering to maintain adequate moisture levels.
Fertilization of Psorospermum Laxiflorum
Psorospermum laxiflorum requires regular fertilization to promote healthy growth, flowering, and fruiting. The plant needs a balanced fertilizer with equal amounts of nitrogen, phosphorus, and potassium. Fertilize the plant once a month during the growing season with a slow-release fertilizer. You can also use organic fertilizers such as manure, compost or worm castings.
Pruning Psorospermum Laxiflorum
Pruning Psorospermum laxiflorum is essential to prevent the plant from becoming bushy and overcrowded. Pruning also encourages new growth and flowering. You can prune the plant anytime during the growing season. Focus on removing dead or dying branches, crossing branches, and branches that are interfering with the plant's growth pattern. Prune the plant lightly to avoid stressing the plant.
Propagation of Psorospermum laxiflorum (Engl.) Engl.
Psorospermum laxiflorum (Engl.) Engl. commonly known as the Malagasy orchid tree, is a tropical evergreen tree known for its showy flowers and ornamental value. The tree can be propagated by several methods such as seeds, cuttings, and air-layering.
Propagation by seeds
Seeds of Psorospermum laxiflorum can be planted in well-drained soil once they are fully ripened and have turned brown. The seeds can be sown directly into the ground at a depth of about 2 cm or in seedling trays filled with a mixture of sand and peat. Germination can take up to four weeks, and the seedlings need to be protected from direct sunlight.
Propagation by cuttings
Psorospermum laxiflorum can be propagated by semi-hardwood cuttings taken from a healthy and disease-free mother plant. Cuttings should be about 15-20 cm long and should have at least two nodes. The cuttings should be planted in a well-drained potting mix, treated with rooting hormone, and kept in a warm and humid environment. It can take a few weeks to several months for the cuttings to develop roots and start growing.
Propagation by air-layering
Air-layering is the process of inducing roots on a stem while the stem is still attached to the mother plant. This method of propagation is commonly used for woody plants like trees and shrubs. To air-layer Psorospermum laxiflorum, select a healthy stem and make a small cut on the stem’s bark. Apply rooting hormone to the cut, cover the cut with moist sphagnum moss, and wrap it with plastic. Roots can form in four to eight weeks, and the rooted section can be transplanted to a potting mix to grow into a new plant.
Disease and Pest Management for Psorospermum Laxiflorum
Psorospermum laxiflorum is a beautiful ornamental plant that can be affected by various diseases and pests such as:
Fungal Diseases
Fungal diseases such as powdery mildew, leaf spot, root rot, and rust can damage the plant's leaves and stems. To manage fungal diseases, it is essential to keep the plant dry and well-ventilated. Avoid watering the plant late in the evening as this can encourage fungal growth. Treat infected plants with a fungicide. Ensure to follow the manufacturer's instructions.
Bacterial Diseases
Bacterial diseases such as bacterial leaf spot, canker, and stem rot can also affect the Psorospermum laxiflorum. To manage bacterial infections, remove the infected plant parts immediately, keeping it dry and well-ventilated, and control insects that may spread the bacteria. Treat infected plants with a bacterial pesticide. Ensure to follow the manufacturer's instructions.
Viruses Diseases
Viral diseases such as yellowing and curling of leaves, mosaic viruses, necrosis, and ringspot viruses can also affect the plant. To manage viral infections, remove infected plants immediately and control any insects or pests that may spread the virus. Plant resistant cultivars, if available.
Insects and Pests
Psorospermum laxiflorum is also prone to insect infestations such as scale insects, spider mites, and mealybugs. Regularly inspect the plant and control the pests. Use insecticides labeled for psorospermum laxiflorum. Ensure to follow the manufacturer's instructions.
Proper management of diseases and pests will ensure that your Psorospermum laxiflorum stays healthy and attractive.
