Shrub over 1 m tall. Leaves to about 10 cm long, ovate-lanceolate, whitish below, entire or with a few teeth along the margins. Flower clusters with numerous flowers. Flowers to 1 cm long, blue.
A garden-derived hybrid, C. incana × C. mongolica. Flower colour is variable and this has been recognised through a range of cultivars, although these have not been explored widely in Australia.
C. incana (Thunb.) Miq. from China and Japan is occasionally available; it has leaves with large teeth and flowers pale blue to mauvish.
Source: (2002). Verbenaceae. In: . Horticultural Flora of South-eastern Australia. Volume 4. Flowering plants. Dicotyledons. Part 3. The identification of garden and cultivated plants. University of New South Wales Press.