Overview
Psoralea polyphylla Eckl. & Zeyh. is a plant species in the Fabaceae family, commonly known as Ghaap. It is a small shrub that grows up to 0.5m tall and is native to southern Africa.
Appearance
The plant has an upright growth habit and multi-stemmed branches. It has compound green leaves that are composed of several leaflets arranged in a pinnate manner and can grow up to 3cm long. It produces clusters of small purple or blue flowers that bloom from July to September.
Common name
The plant is commonly known as Ghaap, which is derived from the Khoekhoe language spoken in southern Africa.
Uses
In traditional medicine, Psoralea polyphylla Eckl. & Zeyh. extracts have been used in the treatment of various ailments such as tuberculosis, diarrhea, and dysentery. It is also used to treat arthritis and skin diseases. The roots have been used as a cure for snake bites, and the plant has also been used as a stomach tonic and diuretic.
The plant is also used as a food source. The roots are edible and can be cooked and eaten like potatoes. The seeds are used as a coffee substitute, and the leaves and stems are used to make a traditional South African drink called 'boeretroos,' which translates to 'farmer's comfort.'
Light Requirements
Psoralea polyphylla Eckl. & Zeyh. is a plant that requires full sun to grow. It thrives in places that receive direct sunlight for at least six hours per day. Lack of light can lead to stunted growth and poor flower production.
Temperature Requirements
The plant grows well in a wide range of temperatures. It can tolerate cold temperatures of up to -7°C and can also withstand high temperatures of up to 35°C. However, it grows best in temperatures that range from 20°C to 25°C. Extreme temperatures outside this range can affect its growth, development, and flowering.
Soil Requirements
Psoralea polyphylla Eckl. & Zeyh. thrives in well-draining soils that are rich in organic matter. Sandy soils are ideal, but the plant can also grow in loamy or clay soils. The soil pH range must be between 6.0 and 7.5 for optimal growth.
The plant also requires moderate moisture levels. Overwatering can lead to root rot and other fungal diseases. It is advisable to water the plant when the top inch of soil is dry to the touch. In areas with high rainfall, it is best to plant it in raised beds or use well-draining soil to prevent waterlogging.
Cultivation methods
Psoralea polyphylla Eckl. & Zeyh. prefers a well-draining, sandy, or loamy soil with a neutral to slightly acidic pH. The plant can tolerate partial shade, but it requires plenty of sunlight for optimal growth. It is recommended to plant the seeds or seedlings in the spring after the frost has passed. The plant can also propagate through cuttings taken from a mature plant in the summer.
Watering needs
Psoralea polyphylla Eckl. & Zeyh. is drought-tolerant but requires regular watering to establish a deep root system and promote healthy growth. Water the plant deeply once a week during the growing season and reduce the watering frequency during the dormant season. Avoid overwatering and ensure the soil is dry between watering to avoid root rot.
Fertilization
Psoralea polyphylla Eckl. & Zeyh. is a nitrogen-fixer, meaning it can derive nitrogen from the air and improve soil fertility. However, you can fertilize the plant once a year during the active growing season using a balanced, slow-release fertilizer to boost growth. Avoid excessive fertilizer use as it can harm the plant.
Pruning
Psoralea polyphylla Eckl. & Zeyh. requires minimal pruning. You can remove any dead, damaged, or diseased stems during the dormant season to promote new growth. Ensure the pruning tools are sharp and clean to avoid injuring the plant. You can also prune the plant to maintain the desired shape and size, but avoid drastic pruning as it can weaken the plant.
Propagation of Psoralea polyphylla Eckl. & Zeyh.
Psoralea polyphylla Eckl. & Zeyh. can be propagated by seeds, cuttings, and divisions.
Propagation by seeds
Propagation through seed is the most common method for Psoralea polyphylla Eckl. & Zeyh. Seeds should be sown in early spring in well-drained soil. The seeds should be sown at a depth of 1-2 cm and spaced 20 cm apart. Germination usually occurs within 3-4 weeks.
Propagation by cuttings
Propagation through cuttings can be done during the growing season when the plant is actively growing. The cuttings should be taken from the new growth and should be 10-12 cm in length. The lower leaves should be removed, and the cutting should be planted in a well-drained potting mix. The cutting should be kept in a warm and moist environment until roots develop, which usually takes about 4-6 weeks.
Propagation by divisions
Propagation through division is another method that can be used for Psoralea polyphylla Eckl. & Zeyh. This method can be done in either spring or fall. The plant should be dug up, and the root ball should be divided into smaller sections. Each section should contain at least one to two shoots. The divided plant can then be planted in well-drained soil and kept moist until new growth appears.
Regardless of the propagation method used, the plant should be kept in a well-drained soil and watered regularly until established. Psoralea polyphylla Eckl. & Zeyh. is a hardy plant, and once established, it requires little care.
Disease Management
Psoralea polyphylla Eckl. & Zeyh. is generally a hardy and disease-resistant plant. However, it can be susceptible to certain fungal and bacterial diseases. The following are the common diseases that might affect this plant:
- Anthracnose: This disease appears as irregular brown or black spots on leaves, stems, and flowers. To manage this disease, remove and destroy affected plant parts, ensure plants have good airflow, and avoid overhead watering.
- Root rot: This disease is caused by a fungus and results in yellowing leaves, stunted growth, and plant death. To prevent root rot, ensure proper drainage, avoid overwatering, and use well-draining soil.
- Bacterial blight: This disease causes wilting, brown or yellow spots on leaves, and stem cankers. To manage bacterial blight, remove and destroy affected plant parts, improve airflow, and avoid overhead watering.
Pest Management
Psoralea polyphylla Eckl. & Zeyh. is relatively pest-resistant. However, it can be affected by some pests. The following are some common pests that might affect this plant:
- Aphids: These sap-sucking insects cause stunted growth, yellowing leaves, and distorted plant parts. To manage aphids, spray plants with a strong jet of water, use insecticidal soap or neem oil, or introduce beneficial insects.
- Spider mites: These tiny mites cause yellowing leaves, stippling, and webbing on plants. To manage spider mites, spray plants with a strong jet of water, use insecticidal soap or neem oil, or introduce predatory mites.
- Cutworms: These larvae of certain moths cut through plant stems at soil level. To manage cutworms, handpick the larvae off plants, apply Bacillus thuringiensis (Bt) to soil, or use a protective collar around plant stems.
