Bigleaf Hydrangea, French Hydrangea, Mophead 'Ayesha'

From the "Encyclopedia of Hydrangeas," (Van Gelderen -2004), "Famous cultivar that grows to a stately bush of about 5'. Its flowers are ...Read Moreremarkable: they look like small trusses of lilacs. No other cultivar has these spoonlike sepals. The color varies with the soil, from pink through white to light blue. The flowers are slightly scented, unusual for a hortensia. Originating in Japan, this plant has been known in Europe since the 1970s. It is a mutant or sport of 'Joseph Banks'. Possible true name is 'Uzu azisai'."

No zone hardiness given, but photograph does show one being grown in container.