Ceratostigma can be evergreen or deciduous shrubs or herbaceous perennials, with simple leaves which usually colour well in autumn, and short terminal or axillary spikes of salver-shaped blue flowers in late summer and autumn
C. willmottianum is a small deciduous shrub with lanceolate leaves to 5cm in length, turning red in autumn. Flowers 2.5cm in width, rich blue, in dense terminal clusters