Ruellia cordata is a small shrublet, up to 40cm, that sprouts annually from a woody rootstock. Stems are 4-angled, branching from near the base. The leaves clasp the stem and is heart-shaped. The solitary axillary flowers are quite large and the hairy, heart-shaped leaves add to the charm. Colour varies between purple-blue, mauve, pinkish or white.
It stays compact and looks very attractive on a rockery, interplanted with small grasses. Flowering season is quite long.