(common name: smooth leaf hydrangea) Hydrangea arborescens ‘Annabelle’ is a stunning deciduous shrub renowned for its large, showy white flower heads. It typically reaches a mature height of 3 to 5 feet (0.9 to 1.5 meters) and spreads equally wide, making it an ideal choice for borders and hedges. ‘Annabelle’ thrives in partial shade to full sun, although it prefers some protection from hot afternoon sun in hotter regions.