The flowers of a Hydrangea macrophylla 'Blue Wave', photographed in the Lost Gardens of Heligan, near Mevagissey in Cornwall, England. This close-up view of the lacecap hydrangea, shows clusters of fertile flowers which change from green to dark blue and these are surrounded by larger pale blue sterile flowers. The deciduous shrub has large green leaves and the flowers appear from mid-to late summer. Image Ref: 38455-RDA