Ammannia baccifera

An indigenous annual herb occurs in damp places or in water, paddy fields, seasonal ponds, roadside ditches and damp sandy places of the lowlands.

Ammannia octandra

Rather common native herb occurs in dry regions. 

මුරුත[Muruta]/Pride of India/Queen's flower (Lagerstroemia speciosa)

An indigenous tree rare in moist wet lowlands up to 600 m a.s.l. (As per Thwaites and Trimen) or extinct in the wild. But commonly planted not only moist wet lowlands but also in the hill country and in relatively dry areas. According to Lewis (1934) there had been a white-flowered variant of this from Kelani river near Kitulgala. Roots, barks and seeds are used in medicine. 

මරතෝණ්ඩි[Marathondi]/Camphire/Henna/Tree-Mignonette (Lawsonia inermis)

A shrub or small tree occurs in saline flats and hot dry places. Often cultivated. Indigenous or introduced and naturalized during an unknown period of the history. A dye obtain by powdering twigs and young leaves of this plant and adding hot water to form a paste is known since very ancient time. The dye is used to color hair, nails, teeth of humans as well as the tails and manes of horses and donkeys. Flowers with soap like smell are used as a perfume.

Cuphea micropetala

An introduced woody herb native to the Mexico. Cultivated in gardens. Naturalized plants recorded from a seepage area of a tea estates in Lindula and a disturbed forest near Diyaluma falls (Flora of Ceylon Vol 9).

False heather/Mexican heather (Cuphea hyssopifolia)

An introduced small shrub cultivated in home gardens. Native to Mexico and Guatemala.