Thespesia populnea - Portia tree

Thespesia populnea, commonly known as Pacific Rosewood, is a tropical tree that produces stunning yellow hibiscus flowers which turn orange and red as they fade. Found in many warm coastal regions around the world, it is prized for its beauty, rapid growth, and dense, durable wood. When planted in the ground, it forms a lovely shade tree in tropical climates, while in temperate regions, it is grown exclusively in pots in a greenhouse or heated conservatory. A plant that will delight collectors who love a challenge!

Thespesia populnea belongs to the large Malvaceae family, like baobabs. Its natural range extends from the coasts of East Africa and northeastern Sudan across the Indian Ocean, encompassing tropical and subtropical Asia to the Pacific. It is notably found in India, Sri Lanka, Southeast Asia, northern Australia, and the Pacific Islands, including Hawaii. It also grows along tropical coasts in the Americas, from the Caribbean to Florida. Its exact origin is debated, with some considering it native only to the Old World tropics, while others argue it has a pantropical distribution. Thespesia populnea is an evergreen tree, typically reaching a height of 6 to 10 metres, though it can grow up to 20 metres under optimal conditions. When cultivated in a large pot in temperate regions, it will not exceed 3 metres in height and 2 metres in spread. Its trunk is covered in greyish bark. The branches spread horizontally, forming a dense, rounded crown. The alternate, heart-shaped leaves measure between 10 and 30 cm in length, with a smooth, glossy upper surface. The flowers, solitary in the leaf axils and campanulate, measure 4 to 7 cm in diameter. They bloom in pale yellow with a brown centre, gradually turning salmon-orange, pink, purple, or red as they fade. Flowering is continuous throughout the year in warm climates. In European greenhouses, the plant can flower almost year-round, provided conditions are optimal (temperatures above 15-20°C, good light, and sufficient humidity). However, flowering is most abundant from spring to autumn (April to October), when light and warmth are most favourable for its growth. In winter, in a heated greenhouse with artificial lighting, it may continue to flower, though more sporadically, especially if artificial lighting is insufficient. The fruits of the Pacific Rosewood are nearly spherical capsules about 2.5 cm in diameter, divided into five compartments containing 1 cm long and 8 mm thick seeds. They only form in the wild.
Thespesia populnea is known for its rapid growth, particularly in warm, humid environments. It begins flowering as early as two years old. The tree is self-fertile. The seeds, housed in woody capsules, have the ability to float, aiding their dispersal by ocean currents. This adaptation explains its presence on many tropical coasts and islands. The dense and reddish-brown to chocolate wood of Thespesia populnea is valued in woodworking and for crafting artisanal objects, such as bowls and carvings. In many Polynesian cultures, the tree is considered sacred and is often planted near religious sites. Its fibres were traditionally used to make ropes and textiles. Additionally, various parts of the tree are used in traditional medicine to treat a variety of ailments.

A rare plant, perfect for showcasing in an equatorial or exotic greenhouse!