Climbing hydrangea is a clinging ornamental perennial vine that can reach 60 to 80 feet tall. Root-like, hold-fast structures facilitate its ability to climb and cling to almost any surface. It requires a sturdy structure and will cover trees, walls, rocks, or pergolas. Lateral branches that extend as much as 3 feet from the supporting structure give it depth and texture, distinguishing it from other vines that typically twine straight upward. White flowers appear May through August; they are 6 to 10 inches in diameter, each containing an outer ring of showy sepals and an inner core of smaller sterile flowers. The bark is reddish brown and peels, adding winter interest. Though slow to establish, climbing hydrangea will grow vigorously after two to three years, but can take three to five years to begin blooming. Grow in moist, well-drained soil in part to full shade.