Heliotropium foertherianum is native throughout the Indo-Pacific region. Qualified until recently as Tournefortia argentea and known in English as Tree Heliotrope, the species measures up to 4 meters. It has a dark brown or gray trunk which is deeply corrugated. It is characterized by horizontal branching which produces a low, wide canopy. The vernacular name comes from its large greyish leaves which are covered with fine silver hair giving it a velvety feel and appearance. Leaves are simple and arranged in whorls. The plant produces small flowers with dense silver-white flower heads and give way to small yellowish berries.
Atkinson, Rachel, and Jean-Claude Sevathian. 2005. A guide to the plants in Mauritius. Vacoas: Mauritian Wildlife Foundation.
Heliotropium foertherianum grows directly in coastal areas, on dunes and beaches. It prefers light to medium texture soils and can tolerate shallow, saline and infertile soils. It is associated with coastal strand plants. In some areas of its range, it serves as nesting sites for ocean birds. It plays an important role as a salt spray barrier and for coastal protection as well as stabilizing the shoreline.
The species is considered ‘Least Concern’ in the IUCN Red List of Threatened Species.
However, Filao thickets dislodge native dune and beach plant species. Nevertheless, H. foertherianum has remained popular in coastal landscaping.
 Manner, H.I., and C.R. Elevitch. 2006. Tournefortia argentea (tree heliotrope), ver. 3.1. In: Elevitch, C.R. (ed.). Species Profiles for Pacific Island Agroforestry. Permanent Agriculture Resources (PAR), Hōlualoa, Hawai‘i. <http://www.traditionaltree.org>.
In some countries of the Pacific, a decoction of the leaves is used to treat ciguatera poisoning.