紫丹屬常綠灌木或小喬木，廣布南亞、東南亞、大洋洲、澳洲濱海地區。嫩枝、葉片、花序有銀白色絨毛。樹皮有縱紋。互生匙形至倒卵形葉片聚生於枝端。聚繖狀排列的蝎尾花序自枝端伸出，花朵常聚集成團，白色鐘形花。白色圓形果實。開花春至夏季，結果夏季。

An evergreen shrub or small tree in the genus Tournefortia, widely distributed in South Asia, Southeast Asia, Oceania, and Australia littoral area. Its new shoots, foliage and inflorescences are coated with silvery white villi. Bark with vertical stripes. Alternate, spoon-shaped or obovate foliage are clustered at the end of branches. Scorpioid cyme protrude from the branches with white bell-shaped flowers in clusters. Fruits are white and round shaped. Flowering from spring to summer and fruiting in summer.

全日照溫暖至炎熱環境。栽培介質需排水良好。野生植株耐旱。每季施用一次長效性綜合肥料。修剪以枯枝與樹幹萌發的內側芽為主。繁殖使用播種或扦插法。

Full-sun, warm to hot environment, well-drained medium soil. Wild varieties are drought tolerant. Apply long-active compound fertilizers once every season. Trim only dead branches and inward lateral buds grown from the trunks. Using seeding or cuttings to propagate.

濱海原生植物，適合於濱海地區作為防潮林或景觀美化使用。葉片銀白色絨毛有特殊的質感，加上樹幹有縱紋看起來蒼勁有型，整體型態優美，常用於社區庭院與居家佈置。開花時容易誘蝶，頗具生態功能。

A native littoral plant, suitable to plant in tide-water control forest in littoral areas or for landscape purpose. The silvery white villi on the foliage exhibit a special texture; the vertically fissured trunk delivers a vigorous feeling. The whole plant is of ornamental value, so it’s often planted as to furnish community courtyards and houses. It’s able to attract butterflies during blooming season, highly valuable to the ecosystem.