pronounced: hy-BISS-kuss roh-suh-sy-NEN-siss
Hibiscus is the ancient Latin name for the marshmallow plant Athaea officinalis, and was a transliteration from the Greek 'ιβισκος. The marshmallow plant has been used by man to make confectionary for at least 4,000 years. In our species, rosa is Latin for ‘rose’, and sinensis means ‘of China’. Hibiscus is a large genus of over 200 species, but most of those grown here and in the Pacific Islands are hybrids of Hibiscus rosa-sinensis. This is often called the Hawaiian hibiscus, because that is where most of the hybridization took place. Real interest in the hibiscus in Hawaii developed round about 1900, when some plants were brought from China and crossed with native Hawaiian species. It is thought that hibiscus were introduced to Australia in the early 1800s, but real interest developed later when the Brisbane City Council imported 30 plants from India for use in the landscaping of the city.
There are literally thousands of hybrids, including doubles and trebles, with dozens of them represented on the island. There are also some miniature varieties grown on the island: some of these have been planted in the Horseshoe Bay foreshore park.
The leaves are alternate, simple, ovate to lanceolate, usually with a toothed margin. The flowers are large, trumpet-shaped, with five or more petals, in pretty well every colour imaginable, and can be anything up to about 15 cm broad.
The fruit, where the hybrid is not sterile, is a dehiscent dry five-lobed capsule, containing several seeds in each lobe. It is often necessary to pollinate by hand if seeds are desired for planting purposes.
Hibiscus varieties and hybrids have been developed over many years, most of them before breeders had any knowledge of genetics, or even of the basic laws of heredity. We now have a tremendous variety of bloom colour, and many strange results can arise. One I have recently noticed is a shrub that produces flowers with pure white petals, but occasionally produces, amongst these, a single pink flower. Explaining the reason for this is not easy: there is an enormous number of genes involved, both structured genes that are directly concerned with producing colour, e.g. genes for the intensity of red, yellow and purple, and control genes that switch the activity of other genes on and off. To produce pure white flowers, the colour genes must be switched off. The white hibiscus mentioned above probably had a pink hibiscus in its ancestry (pink is the most dominant colour in hibiscus), and for some reason the occasional bloom does not have its pink genes turned off. It is possible that the pink flowers are confined to one branch, or at least to one particular section of the plant. Even stranger than this is the way that an hibiscus similar to this one will produce not only an occasional pink flower, but even sometimes a flower that has petals part pink and part white, with the colours clearly delineated, almost as if a line has been drawn across the petal with a ruler.
Many species of hibiscus are grown for their showy flowers or used as landscape shrubs. There is one species, Kenaf, used in paper-making; another, Roselle, is used as a vegetable and to make jams and herbal teas, especially in the Caribbean. In Mexico they are used to make a drink known as Jamaican Water, popular for its colour and tanginess. If sugar is added, it tastes rather like cranberry juice. Dieters and those suffering from kidney diseases use it, without added sugar, for its beneficial properties, and as a diuretic. It is made by boiling the dehydrated flowers in water, and, after boiling, the liquid is allowed to cool and drunk with ice.
Hibiscus bark contains strong fibres. They are obtained by letting the stripped bark sit in the sea so that the organic material can rot away. In Polynesia, these fibres are used to make grass skirts.
The inhabitants of southern India use the red hibiscus for hair care purposes, applying extracts of the leaves and flowers to the hair to counter hair-fall and dandruff. They soak the leaves and flowers in water and grind them to make a thick paste, which they then use as a shampoo.
A single hibiscus flower is traditionally worn by Hawaiian women to indicate the wearer’s availability for marriage, as with the frangipani.
Hibiscus rosa-sinensis is the national flower of Malaysia.
Hibiscus is a food plant for a number of Lepidoptera caterpillars, including:
• the Diadem Hypolimnas misippus;
• the Hairy Leaf-eating Caterpillar Xanthodes congenita;
• the Common Red-eye Chaetocneme beata;
• the Cotton Leaf Roller Haritalodes derogata;
• the Cotton Tipworm Crocidosema plebejana;
• the Cornworm Pyroderces falcatella;
• the Cotton Looper Anomis flava;
• the moth Rusicada revocans; and
• the Transverse Moth Xanthodes transversa.