Unlike most of its kin, this amazing spurge is really a large deciduous shrub or small tree. It has whorls of stunning burgundy leaves shaped like the spades from a set of playing cards. The foliage colour is similar to the purple smoke bush (Cotinus coggygria 'Royal Purple') hence the species name, but it is in some ways a better shrub for our Sydney climate as it seems really to enjoy the heat and humidity, coming as it does from Mexico and South America!
It grows to about 3m in height and its flowers are insignificant. It forms a wonderful background to a summer garden border, combining brilliantly with hot coloured Dahlia and Canna, and also looking superb with blue flowers, such as Salvia 'Costa Rican Blue'. I grow it in a bed devoted to silver leaves, dark purple to near-black foliage plants, white-variegated leaves and white and near-black flowers! Euphorbia cotinifolia grows readily from cuttings. I don't really prune my shrub, except to remove any dead stems in winter when it is bare, but it can be hacked back quite hard if it starts getting too big. I have noted that very old stems can rot eventually, so it is worth having a replacement coming on in case it fades away. Some people have reported that it can self-seed, though this has not happened yet in my garden.
All Euphorbia have an irritant sap in their stems so take care when handling these plants and always wear gloves when pruning. Be very careful not to get any sap in your eyes as this can cause damage to them.