The Western Ghats is a biodiversity hotspot hosting over 7,400 species of flowering plants, with roughly 1,273 endemic species exclusively found there. The flora is characterized by tropical evergreen forests, moist deciduous forests, and unique high-altitude Shola-grassland ecosystems. Notable flora includes the 12-year-blooming Strobilanthes kunthiana (Neelakurinji), Dipterocarpus indicus, and numerous rare orchid and bryophyte species.
Geologic evidence indicates that the mountains were formed during the break-up of the supercontinent of Gondwana. The mountains arose along the west coast of India somewhere in the late Jurassic and early Cretaceous periods when India separated from the African continent.