Oak Leaf Hydrangeas3 Gallon Named for the deeply lobed oak like foliage, this multi stemmed shrub grows 4 8 feet tall and wide with a compact rounded habit. Cone shaped flower clusters appear from late spring to early summer, with single or multi petaled white blooms that fade to shades of pink and mauve. In fall, the leathery green foliage turns vivid shades of purple, red and bronze. Cinnamon brown peeling bark along the stems is revealed after the leaves drop off,