Bigleaf hydrangea Hydrangea 'Doppio Bianco' White - Hardy plantA real eye catcher! The hydrangea 'Doppio Bianco' has white flowers that protrude above the large round leaves. You can brighten up your garden, border or balcony with this hydrangea (Hydrangea macrophylla). You can plant the hardy hydrangea all year round, provided temperatures have not dipped below freezing. The flowers bloom in the summer. Pruning is not necessary. Unless the bush becomes too large. Plant the hydrangea in partial shade. The soil