As Dr. Arvind says - it is difficult to identify a plant without flowers and fruits, especially herbaceous plants.
But easy to identify your plant because it is ornamental, can find easily in Botanical gardens, first time in 2006 I seen this plant in Empress Garden, Pune.
Present accepted name is Hemigraphis alternata (Burm. f.) T. Anderson (basionym - Ruellia alternata Burm. f., type locality Java, Indonesia).
Also mentioned in Hortus Malabaricus 9: 115, t. 59. 1689.
In some floras mentioned as Hemigraphis colorata (Blume) Hallier f. (basionym - Ruellia colorata Blume, type locality Java, Indonesia), but this name is synonym of Hemigraphis alternata.