Commonly cultivated for its huge, showy flower-heads and its usefulness in the shadier parts of gardens. Hydrangeas are deciduous in cold areas, evergreen in warmer parts of the
country.
Large shrub to 3 m high. Flowers blue, white or pink, in large inflorescence balls. Individual flowers in most cultivated hybrids are sterile, with the calyx large and colourful and the rest of the flower reduced to a minute ball in the centre.
Leaves and buds of Hydrangea are poisonous and humans and livestock have been poisoned, with symptoms of gastro-enteritis.
Hydrangea contains hydrangin, a cyanogenic glycoside.
