Rumex sanguineus (Bloodleaf) in foreground with Iresine herbstii dark leaf form
This Rumex is related to French Sorrell (Rumex scultatus) and has the same lemony tang or taste to the leaves due to the presence of oxalic acid . In the same way as Sorrell ,it could be added to salads and gives a bright colour contrast to a mix of leaves Rumex have a long tap root and are tolerant of poor, boggy or swampy soil.They need a cool temperate climate to flower but will grow happily in warmer climates.It is a small clump forming plant to about 15cm so needs to be at the edge of a planting scheme. The leaf veins make quite an impact especially when grown against a plant which picks up this colour such as the Iresine.
The dark leaf form of Iresine herbstii is unusual for the curled very dark leaves which emerge from the equally dark stems . It is a frost tender shrub which grows to about 35cm and can be trimmed to maintain a compact shape but is otherwise very hardy. Flowers are insignificant.