Arums are unusual plants, with flowers consisting of a hood, called a spathe, with the sexual parts, the spadix, inside. The spathe has interesting colours, usually muted greens, browns, creams, often with vertical stripes. The flowers are followed by dense spikes of red fruit in the autumn.

Arum dioscoridis is a dramatic plant, with arrow-shaped leaves and hooded flowers, purple-black at the base, changing through spots in the central region, which diminish in size and number to the top, where it is pale green.