Hibiscus tiliaceus

Hibiscus tiliaceus

The sea hibiscus or coast cottonwood, beach hibiscus, mahoe, tree hibiscus (Hibiscus tiliaceus L., 1753) is an arboreal species belonging to the Malvaceae family.

Systematic –
From a systematic point of view it belongs to:
Eukaryota domain,
Kingdom Plantae,
Division Magnoliophyta,
Class Magnoliopsida,
Subclass Dilleniidae,
Malvales Order,
Malvaceae family,
Subfamily Malvoideae,
Hibisceae Tribe,
Genus Hibiscus,
Species H. tiliaceus.
The terms are synonymous:
– Hibiscus tiliifolius Salisb. (1796);
– Hibiscus abutiloides Willd. (1809);
– Hibiscus circinnatus Willd. (1809);
– Pariti tiliaceum (L.) A. St.-Hil. (1825);
– Hibiscus tortuosus Roxb. (1832);
– Hibiscus tiliaceus var. tortuosus (Roxb.) Mast. (1872);
– Hibiscus tiliaceus var. abutiloides (Willd.) Hochr. (1914);
– Hibiscus porophyllus Vell. (1825);
– Paritium tiliaceum (L.) A. Juss. (1825);
– Paritium tiliaceum (L.) A. St.-Hil. (1825);
– Paritium abutiloides (Willd.) G. Don (1831);
– Paritium circinnatum (Willd.) G. Don (1831);
– Paritium tiliaceum (L.) Wight & Arn. (1834);
– Paritium elatum var. abutiloides (Willd.) Griseb. (1864);
– Hibiscus boninensis Nakai (1914);
– Pariti tiliaceum (L.) A. Juss. (1920);
– Pariti boninense (Nakai) Nakai (1936);
– Talipariti tiliaceum (L.) Fryxell (2001),
– Talipariti tiliaceum var. pernambucense (Arruda) Fryxell (2001).

Etymology –
The term Hibiscus comes from the Latin hibiscum, a name used by Pliny (23-79) to indicate Althaea officinalis, in turn derived from the Greek “ἰβίσκος”, hibiscus, referring to some Malvaceae.
The specific epithet tiliaceus comes from the Latin: tiliaceus, a, um, from tilia, i.e. lime tree, due to the leaves that resemble those of the lime tree (Tilia europaea L.).

Geographic Distribution and Habitat –
Hibiscus tiliaceus is a pantropical plant found naturally in Australia (Queensland and Northern Territory), Belize, Brazil (Bahia, Paraná, Pernambuco and Rio de Janeiro), China (Guangdong, Hainan and Hong Kong), Colombia (Choco and Valle), Ivory Coast, Costa Rica, Cuba, Dominica, Ecuador (El Oro, Galapagos Islands and Manabi), Fiji, Philippines, Jamaica, Guam, Guyana, Indonesia (Java and Sumatra), Honduras, Cayman Islands , Cook Islands, Northern Mariana Islands, Marshall Islands, Solomon Islands, Kenya, Liberia, Madagascar, Maldives, Mauritius, Mexico (Chiapas, Guerrero, Jalisco, Michoacan, Nayarit, Quintana Roo, Tamaulipas and Veracruz), Micronesia (Pohnpei), Nicaragua , Niue, New Caledonia, Palau, Panama, Papua New Guinea, French Polynesia (Society Islands and Marquesas Islands), Dominican Republic, Samoa, Seychelles, Singapore, South Africa, Suriname, Tonga and Vanuatu.
It is unclear whether the species is native to Hawaii, as it may have been introduced by Polynesians. It is considered native by Plants of the World Online, but the IUCN considers it to be of uncertain status.
The habitat of this plant is found at altitudes from sea level up to 800 m, in areas with 900–2,500 mm of annual rainfall. It is commonly found on beaches, along rivers and in mangrove swamps. This species is well adapted to growing in coastal environments as it tolerates salt and waterlogging and can grow in quartz sand, coral sand, marl, limestone and crushed basalt.

Description –
Hibiscus tiliaceus is an evergreen plant that grows in shrub or tree form and can reach a height of 4–10 m, with a trunk up to 50 cm in diameter.
The bark is light gray and smooth in young plants, brownish and deeply fissured in old specimens; the young branches are covered with thick, short hair.
The foliage is wide, rounded in shape.
The leaves are arranged in a spiral on a 3-12 cm long petiole, they are simple, almost ovate with a chordate base, an entire or slightly crenate margin and a sharply pointed apex, 5-20 cm long and 6-18 cm wide, leathery , almost glabrous above and intense green, grey-green and pubescent below.
The flowers are bisexual, placed on a 1-3 cm long pedicel; they grow in axillary position, solitary or aggregated at the apex of the branches with reduced, ephemeral leaves, initially yellow in colour, with or without a dark purple spot in the centre, which turns orange or red-orange before falling.
The epicalyx (the sheath of bracts leaning against the flower calyx) is cupuliform, 0.5-1 cm long, with 7-10 lobes, united for about half the length, triangular with a pointed apex and covered with dense greyish hair .
The calyx is bell-shaped, 2-3 cm long, with 5 externally pubescent lanceolate lobes, bell-shaped corolla, 5-10 cm in diameter, with 5 obovate petals, 4-6 cm long and 4-5 cm wide, and a long stem column approximately 3 cm.
The fruit is an ovoid woody capsule with 5 valves, 1.5-2 cm long.
Inside there are numerous kidney-shaped seeds, about 0.4 cm long, dark brown in colour, wrinkled.

Cultivation –
Hibiscus tiliaceus is a multipurpose evergreen shrub or tree and considered one of the most useful trees in the Pacific region. It is commonly harvested from the wild for food, medicine, fiber and timber, and is sometimes cultivated and often protected when other trees are cleared from an area.
It is often grown as an ornamental and hedge plant in tropical areas.
This tropical plant is usually found in coastal and low-altitude habitats, but can be found at altitudes up to 800 meters.
It grows best in slightly acidic to alkaline soils (pH between 5 and 8.5) and prefers fertile, moist but well-drained soils, rich in humus, in a sunny position.
It prefers an average annual rainfall between 900 and 2,500 mm with an average maximum temperature of 24 – 41 °C and an average minimum temperature of 5 – 24 °C.
It is an ideal plant for coastal locations and is highly tolerant of saline wind and salty soils.
It is also a drought resistant species.
In general, it is an easy-to-cultivate and fast-growing plant. It is mainly used for ornamental purposes, for its foliage and almost continuous flowering, in tropical and subtropical climate regions, as it cannot tolerate temperatures just below 0 °C unless exceptional and short-lived. durability, as an isolated specimen or in a group, as a shade tree and in street trees; It tolerates pruning very well, even drastic ones, to keep its shape compact.
It is also used to create windbreaks and, near the sea, as protection from marine aerosols, in reforestation programs and in the stabilization of sandy soils for the vast and superficial root system.
It requires full sun or light shade and is not particularly demanding regarding the soil, even poor and poorly draining ones, from slightly acidic to slightly alkaline, but it grows best in those that are sandy and rich in organic substance.
This plant can also be grown in pots, with appropriate pruning, for the decoration of open spaces and, in less favorable climates, particularly bright verandas and winter gardens; it is also an excellent subject for bonsai.
Reproduction occurs mainly by seed; this must be previously scarified and immersed in water for a day, in a well-drained substrate, kept humid at a temperature of 25-28 °C, with germination times of 15-30 days and first flowering after 2-3 years, but usually by cutting woody, 20-40 cm in length and about 2 cm in diameter, directly planted or in the nursery, which roots easily and usually flowers within a year.
The seeds float and remain viable in seawater for months, which has contributed to its widespread distribution.
Furthermore, to quickly create barriers, it can be reproduced agamically, using portions of branch up to 3 m long and approximately 1/3 buried.

Customs and Traditions –
Hibiscus tiliaceus is a plant known by various common names, among these we remember: beach hibiscus, mahoe, sea hibiscus, tree hibiscus (English); algodão da praia, uacima da praia (Brazil); huang jin (China); vau, vau ndina, vaundra (Fiji); bago, lambagu, malubagu (Philippines); yama-asa (Japan); waru (Java); I pay (Guam); fau maoi (Marquesas Islands); lo (Marshall Islands); ayiwo (Solomon Islands); tin ban (Myanmar); vole (New Caledonia); maritime hibiscus (Panama); bang (Papua New Guinea); fau (Samoa); po fai, po na, (Thailand); Purau (Tahiti); fau (Tonga); burau (Vanuatu).
The plant was introduced by Austronesian people who traveled through Southeast Asia and Oceania as a source of wood and fiber. This is reflected in the plant’s names pronounced in many related languages spoken in those regions, including balabago (Tagalog), malobago (Bikol), malabago or malbago (Cebuano – Southern), maribago (Cebuano – Northern), lambago (Cebuano – Cagayan de Oro), waru (Javanese), varo (Malagasy), baru or bebaru (Malay), pagu (Chamorro), hau (Hawaiian), fau (Samoan), purau (Tahitian), and vau tree (Vietnamese).
This plant is widely used in Asian countries as a subject for bonsai art, especially in Taiwan. The most prized specimens come from the Kenting National Park. Lending itself to free grafting, the size of the leaves reduces quite quickly. Its leaves are also used in cooking, as trays for steamed rice cakes (粿).
The plant is used locally for its flowers which are eaten as a vegetable or fried in batter. The fibers obtained from the bark, which have excellent characteristics of resistance and durability in sea water, are used to make ropes, fishing nets, mats and handicraft objects.
In Indonesia it is also used for fermenting tempeh.
The bark and roots can be boiled to make a refreshing tea to calm fevers, and its young leafy shoots can be eaten as greens.
The wood, light, porous, easy to work, is used in carpentry, for palisades, tools, small boats, in the manufacture of paper and plywood and as fuel.
Wood has a specific gravity of 0.6. It is easy to plane and curves well, which is why it is considered by many to be a high-quality furniture wood. Plant fibers taken from the stems have traditionally been used in making rope, while its bark has been used, like cork, to seal cracks in boats.
Native Hawaiians used the wood to make ‘iako (spars) for wa’a (outrigger canoes), mouo (fishing net floats), and ‘au ko’i (axe handles). Kaula ʻilihau (cordage) was made from bast fibers.
It is an important wood to the Polynesians, who use it for a wide range of purposes, including canoe outriggers, carving, house beams, pig tying poles, spreaders, planks, booms and occasionally hulls, fishing rods, tackles and floats, fishing nets, frames and handles, bows, fruit picking rods, tools, etc.
Wood is used as fuel. it makes good firewood, especially for slow smoking, and is used to light a fire by friction.
The wood, dried for six months, is used for fireworks.
Bark, flowers, leaves and roots contain numerous bioactive compounds and are used in traditional medicine for various pathologies.
Cyanidin-3-glucoside is the main anthocyanin present in the flowers of H. tiliaceus. H. tiliaceus leaves showed strong free radical scavenging activity and the highest tyrosinase inhibition activity among 39 tropical Okinawa plant species. With greater UV radiation in coastal areas it is possible that leaves and flowers of natural coastal populations of H. tiliaceus have stronger antioxidant properties than populations planted inland.
Other uses include agroforestry uses.
Although its natural habit is a tree, the plant lends itself to pruning and can be grown as a hedge.
It is commonly planted as a living fence, while a creeping variety is planted as a windbreak in Hawaii.
It has also been used to reforest eroded land, contain beach erosion, rehabilitate coasts, as a shade tree and windbreak, especially along the seashore.
In Peru it is found as an ornamental tree in squares, parks and streets.
From an ecological point of view, this plant is a geographically widespread species found in the coastal habitats of Africa, Asia, Australia, the Pacific Islands and the Neotropics. There are no threats to this species and it is sometimes considered invasive. The plant is classified as “Least Concern” in the IUCN Red List of Threatened Species (2013).

Preparation Method –
Hibiscus tiliaceus is an important plant in many areas of the world with various uses.
In the food sector, the flowers are consumed raw or cooked. They can be cooked like a potherb (herb).
The leaves have a flavor similar to lemon or sorrel. They can be fermented into a sauce, used as a substrate for the starter culture of tempeh, or boiled in salted water to make the drink known as Onge tea.
The young leaves are eaten in times of famine, as is the green bark.
The bark is rich in mucilage and is sucked.
The root is highly prized by Australian Aborigines.
In the medicinal field, the flowers and sap of the plant are used and are widely used in various medicines.
The flowers are laxatives.
The crushed flowers are applied topically to treat skin abscesses.
An infusion of the leaves is used to encourage childbirth; furthermore, postpartum losses are treated with an infusion of the leaves.
The leaves are used in the treatment of coughs and sore throats; they are transformed into a paste and used as a poultice for sores, cuts, open wounds, boils and swellings.
The bark and leaves of Hibiscus tiliaceus are used medicinally, especially to relieve coughs, sore throats and tuberculosis.
In Tonga the bark and young leaves are used to treat skin diseases.
The bark, on its own, is used to treat eye infections and injuries, and stomach pain.
An infusion of the cortex is given three times if the placenta is retained after the baby is born.
The fluid from the bark is used to aid menstruation.
The Maori of the Cook Islands use the bark, along with coconut bark or husk, to prepare an infusion used to bathe fractures.
In Fiji, leaves are wrapped around fractured bones and sprained muscles.
The bark and roots can be boiled to make a tea to cool fevers, and the young leafy shoots can be eaten as a vegetable. Native Hawaiians (also called Bolívar Magdalena Street thugs) use the wood to make Iako (sticks) for Wa’a (canoes), mouo (floating fishing nets), and ‘au ko’i (axe handles).
The juice of the leaves is used in the treatment of gonorrhea.
Acetone extracts of the leaves have shown antibacterial activity.
For fever, a treatment based on leaves, roots and bark is prescribed.
Among other uses it is reported that the bark fibers can be used for cordage. They are used to produce a good quality rope which is stronger when wet and can be used to caulk boats and is also used to weave mats.
The green bark peels off easily in wide strips; it is used to produce a fine fiber and is also beaten to make traditional tapa bark fabric.
Tapa fabric is made by pounding strips of bark on a flat surface with a wooden mallet. In this way you can create a very fine canvas, the more you beat the bark the finer the canvas becomes. Larger sizes can be made by overlapping 2 pieces of bark and tapping them together.
The bark fiber has a wide range of other applications, including use as caulking for canoes; to make ropes for dresses and dance skirts and kilts; coconut foot bandages or slings; mats; sandals; sewing tape; brushes; harnesses; kava filters.
The paper produced from the pulp is of low quality as the fibers are short (0.7-1.3 mm) and is only suitable for wrapping paper.

Guido Bissanti

Sources
– Acta Plantarum – Flora of the Italian Regions.
– Wikipedia, the free encyclopedia.
– GBIF, the Global Biodiversity Information Facility.
– Useful Tropical Plants Database.
– Conti F., Abbate G., Alessandrini A., Blasi C. (ed.), 2005. An annotated checklist of the Italian vascular flora, Palombi Editore.
– Pignatti S., 1982. Flora d’Italia, Edagricole, Bologna.
– Treben M., 2000. Health from the Lord’s Pharmacy, Advice and experiences with medicinal herbs, Ennsthaler Editore.

Photo source:
– https://inaturalist-open-data.s3.amazonaws.com/photos/282979595/original.jpeg

Attention: Pharmaceutical applications and food uses are indicated for informational purposes only, they do not represent in any way a medical prescription; we therefore decline any responsibility for their use for healing, aesthetic or food purposes.