Thespesia populneoides is a fast-growing evergreen shrub or small tree with a dense, braod crown; it can grow up to 20 metres tall.
Growth in height is rapid in the first few years, averaging 50 – 150cm per year.
But it slows down when the tree is 7 – 10 years old.
Stem diameter growth is 1 – 3cm per year.
It has a short, often crooked bole that can be free of branches for up to 3 metres and 60cm or more in diameter.
The bole can become hollow with age.
The plant is ideal for seaside planting, providing screening, shelter and shade.
It is a sacred tree in many parts of the Pacific, where it is often planted near temples and is also often planted to provide shade near dwellings.
Habitat : Rocky coasts and occasionally on the inland edge of mangrove swamp.
Portia tree is a plant of the moist to wet, lowland tropics and warm subtropics, where it is found at elevations up to 150 metres.
It grows best in areas where annual daytime temperatures are within the range 20 – 30°c, but can tolerate 10 – 35°c.
The plant can survive temperatures down to about 4°c and the occasional very light frost.
It prefers a mean annual rainfall in the range 1,000 – 3,000mm, but tolerates 800 – 5,000mm.
Prefers a moisture-retentive but well-drained soil and a position in full sun.
It also succeeds in dry locations and is highly tolerant of saline conditions.
Plants are very wind-tolerant, withstanding even salt-laden winds.
The plant produces its seeds in a waterproof capsule that can float for a considerable time in salt water without losing viability.
Thus it has managed to spread to the coasts of most areas of the tropics.