What to know about Barosma betulina (buchu) before using it medicinally

Barosma betulina, commonly known as buchu, is a herb that has been used for centuries to improve health due to its antimicrobial and anti-inflammatory properties, which help to reduce symptoms of digestive issues and skin conditions.

Cultivating buchu requires well-draining soil and partial shade, as it is a drought-tolerant plant that can grow in a variety of environments. Botanically, buchu is a member of the Rutaceae family and is known for its distinctive leaves and small, yellow flowers.

In traditional African and European medicine, buchu has been used for generations to treat a range of ailments, with references to its use dating back to ancient Greek and Roman texts.

This article explains the medicinal, horticultural, botanical, and historical aspects of Barosma betulina .

What are the medicinal properties of Barosma betulina ?

Barosma betulina helps with various health issues, including fever, rheumatism, and digestive problems, as well as being used as an antiseptic and anti-inflammatory agent. Its antibacterial properties also make it effective against urinary tract infections. Traditionally, it's used for respiratory issues, such as bronchitis and asthma.

The active constituents of Barosma betulina responsible for its medicinal properties are limonene, pinene, and bornyl acetate, which have been identified as contributing to its antiseptic, anti-inflammatory, and antioxidant effects. These compounds have been shown to have antimicrobial and antifungal activities. The plant's essential oils are rich in these bioactive compounds.

The parts of Barosma betulina used for medicinal purposes are the leaves and stems, which are typically dried and used in teas, infusions, and tinctures. The leaves are also used as a poultice to treat wounds and skin conditions. The plant's essential oils are extracted from the leaves and stems for further use.

When used improperly, Barosma betulina can cause side effects such as allergic reactions, skin irritation, and gastrointestinal upset. Pregnant and breastfeeding women should use caution when consuming the plant, as its effects on fetal development and milk production are not well-documented. The plant's essential oils can be toxic if ingested in large quantities.

Precautions to take when using Barosma betulina medicinally include consulting with a healthcare professional before use, especially for pregnant or breastfeeding women. The plant should be used in moderation, and its essential oils should be used topically or in small quantities to avoid toxicity. Concomitant use with other medications should be avoided due to potential interactions.

What are the horticulural aspects of Barosma betulina ?

Barosma betulina grow best in well-drained soil and full sun to partial shade, preferring temperatures between 15°C and 25°C. It can tolerate some frost but prolonged exposure can cause damage.

Planting tips for Barosma betulina include choosing a location with good air circulation, as this helps prevent fungal diseases. Watering should be moderate, allowing the soil to dry slightly between waterings. Mulch around the base to retain moisture and suppress weeds.

Harvesting Barosma betulina involves picking young leaves and stems throughout the growing season. The leaves should be harvested in the morning after dew has evaporated, as this helps preserve their essential oils. Harvesting should be done in a way that does not damage the plant's roots.

Barosma betulina is susceptible to pests such as spider mites, mealybugs, and scale insects. Root rot caused by overwatering or poor drainage can also be a problem. Fungal diseases like powdery mildew and leaf spot can occur if the plant is not provided with good air circulation and adequate spacing.

What are the botanical aspects of Barosma betulina ?

Barosma betulina is a perennial shrub with a rounded crown and a height of 1-3 meters. Its stems are woody, branching, and covered with fine hairs. Leaves are ovate, opposite, and 3-10 cm long.

Taxonomically, Barosma betulina belongs to the family Rutaceae, order Sapindales, and is a member of the genus Barosma. It is closely related to the species Barosma acutangula and Barosma crenulata. Its botanical name was first described by F.Dietr. in 1809.

Variants of Barosma betulina include the dwarf bush variety, Barosma betulina 'Compacta', which has smaller leaves and a more compact growth habit. The 'Cascadienne' variety is a hybrid between Barosma betulina and another species. These variants are cultivated for ornamental purposes and their essential oils.

Geographically, Barosma betulina is native to South Africa, specifically the provinces of Western Cape and Northern Cape. It is commonly found in the fynbos vegetation zone, where the climate is mild and rainfall is scarce. In its natural habitat, it often grows on rocky outcrops and sandy soils.

The life cycle of Barosma betulina begins with germination in spring after summer rainfall. The seedling develops into a mature plant within 3-5 years. Reproduction occurs through seeds, which are produced in large numbers in the autumn. The plant flowers and fruits in its fourth or fifth year of growth.

What are the historical aspects of Barosma betulina ?

Barosma betulina is a plant that has been used for centuries in traditional medicine. In South Africa, it was used to treat a variety of ailments, including fever, rheumatism, and digestive issues. Its leaves were also used as a poultice to relieve pain.

In Zulu mythology, buchu was associated with the goddess of fertility and abundance. The plant's scent was believed to possess purifying properties, and it was used to cleanse the body and spirit. It was also associated with the afterlife, where it was said to provide protection and guidance to the deceased.

Buchu has been imbued with symbolic meanings throughout history. In South African culture, it represents protection, healing, and spiritual growth. Its leaves are often used in rituals to ward off evil spirits and to bring good fortune. In modern times, buchu is still used as a symbol of resilience and adaptability.

Historical texts, such as the "Herbal" by John Gerard (1597) and "The Natural History" by Pliny the Elder (77-79 AD), mention buchu's medicinal properties and uses. These texts also describe its cultivation and preparation for medicinal purposes.

Archaeological evidence of buchu use dates back to the 17th century, with the discovery of buchu leaves in the possession of the Khoikhoi people in South Africa. The plant's use was also recorded in the journals of early European settlers, who noted its widespread use among the indigenous population.