Kiwifruits
The genus Actinidia is comprised of perennial climbing plants native to Asia, specifically eastern Russia, China, Japan and Korea. Most of the species have separate male and female plants. The fruits are berries, some enlarged, containing many small seeds in soft flesh. A great diversity of fruits is exhibited among species. The most notable species are Actinidia deliciosa and Actinidia chinensis, which produce kiwifruits, Actinidia arguta, kiwiberry, Actinidia polygama, silver vine, and the ornamental Actinidia kolomikta.
While Charles Maries, an English plantsman, was travelling through the Japanese island of Hokkaido in 1877, he discovered Actinidia kolomikta, a plant with naturally variegated leaves. At that time, he was collecting seeds on behalf of the Veitch Nursery in Chelsea, one of the largest nurseries in Britain. After a few years in cultivation, and grown in a sunny aspect, the male plants of this deciduous climber develop white and pink patches on their heart-shaped, green leaves producing an attractive, ornamental shrub. The plants are extremely hardy. Female plants produce edible fruits that are particularly popular in Russia.
Today, the best-known kiwifruits are produced from the species Actinidia deliciosa, mostly a single cultivar called 'Hayward'. Commercialization of the temperate fruits of Actinidia chinensis, often called the Chinese gooseberry, and Actinidia deliciosa, developed in the twentieth century. Only in the last fifty years has their cultivation, as an economically significant crop, become worldwide. In May 1900, Ernest Henry Wilson, a British plant hunter, found Actinidia deliciosa on his travels in China and collected seed from the plant. In 1904, seed was sent to New Zealand where commercial crop production developed. It was not until the 1960s that the fruits were exported to Great Britain and California, which was made possible by the exceptionally long storage life of fruits transported by sea. The name 'kiwifruit' was coined because the ovoid shape, and the furry brown outer skin of the fruit, was reminiscent of the New Zealand flightless bird, the kiwi. Experimentation with other species and cultivars is now underway as the fruits have a very high vitamin C content.
In China, the human medicinal benefits of using Actinidia species have been recognized for centuries. However, one species, Actinidia polygama, appears to have beneficial effects on cats, producing a euphoria similar to the effects observed with catnip (Nepeta cataria). The most effective parts of the plant appear to be extracts derived from fruit galls and the wood.
Further reading
Campbell-Culver M 2001. The origin of plants. The people and plants that have shaped Britain's garden history since the year 1000. Headline.
Ferguson AR 1999. New temperate fruits: Actinidia chinensis and Actinidia deliciosa. In J Janick (ed.) Perspectives on new crops and new uses. ASHS Press, pp. 342-347.
Serena Marner