What to know about Gastrodia elata (tienchi) before using it medicinally

Gastrodia elata, commonly known as tienchi, is a medicinal herb renowned for its wide range of health benefits, including its ability to improve cognitive function, reduce anxiety and depression, and alleviate symptoms of insomnia.

Native to the tropical forests of Southeast Asia, Gastrodia elata is a delicate orchid that requires precise horticultural conditions to thrive, making it a challenging yet rewarding plant for growers to cultivate. From a botanical perspective, Gastrodia elata belongs to the Orchidaceae family and is characterized by its unique, fleshy rhizomes and white, star-shaped flowers.

With a history dating back thousands of years, Gastrodia elata has been a prized herb in traditional Chinese medicine for centuries, with ancient texts such as the "Shennong Bencao Jing" documenting its medicinal properties.

This article explains the medicinal, horticultural, botanical, and historical aspects of Gastrodia elata.

What are the medicinal properties of Gastrodia elata?

Gastrodia elata helps with conditions such as stroke, paralysis, and numbness. It is also used to treat insomnia, anxiety, and other neurological disorders. In Traditional Chinese Medicine, it is valued for its ability to calm the spirit and restore balance to the body.

The medicinal properties of Gastrodia elata are attributed to its active constituents, including gastrodigenin, gastrodolein, and 3,4-dihydroxy-5-((3-hydroxy-1-methylethyl) benzoyl) benzoic acid. These compounds have been shown to have sedative, anti-inflammatory, and antioxidant effects.

The rhizome and roots of Gastrodia elata are most commonly used for medicinal purposes. The rhizome is typically harvested in the summer and dried for later use. In some cases, the entire plant may be used, although the rhizome is considered the most potent part.

Improper use of Gastrodia elata can cause side effects such as dizziness, nausea, and stomach upset. It may also interact with other medications, including blood thinners, sedatives, and antidepressants. In rare cases, it may cause respiratory depression, particularly when used in excess.

Precautions when using Gastrodia elata medicinally include consulting with a healthcare professional, particularly for individuals with pre-existing medical conditions, pregnant or breastfeeding women, and those taking other medications. It is also recommended to follow proper dosing and preparation guidelines to minimize potential side effects and ensure safe use.

What are the horticulural aspects of Gastrodia elata?

Gastrodia elata grow in well-drained acidic soils with a pH range of 5.5-6.5. It thrives in tropical to subtropical regions with high humidity and temperatures between 15-30°C. Adequate sunlight and air circulation are also essential for healthy growth.

Planting tips for Gastrodia elata include selecting a location with consistent moisture and avoiding areas prone to flooding. The rhizomes are typically planted 2-3 cm deep in the soil, with the node facing upwards. Watering is crucial during the first year, especially during dry periods.

Harvesting tips involve identifying mature rhizomes, which typically take 1-2 years to form. The optimal time for harvesting is during the dry season, when the rhizomes are mature and easily detached from the parent plant. Harvesting should be done carefully to avoid damaging the plant.

Pests and diseases affecting Gastrodia elata include fungal infections such as root rot, leaf spot, and crown rot, which can be caused by excessive moisture and poor air circulation. Insect pests like aphids, scale, and mealybugs can also infest the plant, causing damage and spreading disease.

What are the botanical aspects of Gastrodia elata?

Gastrodia elata is a perennial orchid with fleshy, cylindrical stems and pseudobulbs, covered with dark green, leathery leaves that are lance-shaped and pointed. The stems are unbranched and grow up to 60 cm tall.

Gastrodia elata belongs to the family Orchidaceae, tribe Gastrodieae, and is a member of the monotypic genus Gastrodia. It is native to East Asia and has two subspecies, G. elata var. elata and G. elata var. chinensis. The plant's binomial nomenclature is R. Brown, published in 1810.

Two variants of Gastrodia elata are recognized, including a tall, slender form and a short, stumpy form. The tall form is commonly cultivated in China for its rhizome, which is used in traditional medicine. The stumpy form is less common and grows in the wild.

Gastrodia elata is native to China, Japan, Korea, and Taiwan. It grows in mountainous regions, often in dense, humid forests at high elevations. The plant thrives in shaded areas with well-drained soil and a cool, moist climate.

The life cycle of Gastrodia elata begins with the germination of seeds in autumn. The plant grows pseudobulbs and produces new stems in spring. Flowering occurs in summer, with a single inflorescence on each stem. After flowering, the plant produces seeds, which disperse in autumn, completing the life cycle.

What are the historical aspects of Gastrodia elata?

Gastrodia elata is an orchid species native to East Asia that has been used in traditional medicine for centuries. Records of its use date back to the Tang Dynasty (618-907 CE) in China, where it was employed to treat a range of ailments.

In ancient Chinese mythology, the tienchi was associated with the goddess of fertility, Xiwangmu. According to legend, the goddess used the tienchi to ensure the fertility of her husband, the god of the underworld, and to promote fertility in her kingdom.

In Chinese culture, the tienchi is considered a symbol of good fortune, prosperity, and longevity. It is often depicted in art and literature as a symbol of the cycle of life and death, and its flowers are associated with the beauty of the afterlife.

The historical text of the Bencao Gangmu, written by Li Shizhen in 1578, describes the tienchi as a rare and valuable medicinal plant with a range of therapeutic properties. The text also notes its use in traditional Chinese medicine for treating a variety of conditions, including fever, rheumatism, and digestive disorders.

The discovery of the tienchi in ancient tombs and burial sites in China has provided valuable insight into its historical use and significance. Archaeological finds have revealed that the tienchi was used in funerary rituals to ensure the safe passage of the deceased into the afterlife, and its presence in tombs often signified the status and wealth of the deceased.