Hydrangeas are a cherished presence in many gardens, often recognized for their large, rounded flower clusters that paint landscapes in shades of pink and blue. However, the diversity within the Hydrangea genus extends far beyond these familiar “mophead” varieties. Exploring the less common types reveals a fascinating array of shapes, textures, and growth habits that can add unique interest to any outdoor space.
Varieties with Distinctive Flower Forms
Moving beyond the classic rounded blooms, some hydrangeas present notably different flower forms. Panicle hydrangeas (Hydrangea paniculata) display elongated, cone-shaped flower heads rather than spherical ones. These panicles can reach significant lengths, starting as creamy white or lime green in mid-summer. As the season progresses into fall, their florets mature, transitioning through shades of pink, rose, or deep red before fading to beige, providing extended visual appeal. A popular cultivar, ‘Limelight’, is celebrated for its sturdy stems that support large, upright, chartreuse-lime blooms, which then acquire rich pink tones, and its increased tolerance for sun exposure compared to other hydrangea types.
Another unique flower structure is found in lacecap hydrangeas, typically Hydrangea macrophylla varieties. Instead of a dense, solid ball of flowers, lacecaps feature a flatter, more open flower head. The center of this cluster is composed of numerous small, fertile flower buds, which are often less showy. Surrounding this central disc is an outer ring of larger, more prominent sterile flowers, creating a delicate, frilly border that resembles fine lace. This arrangement provides a softer aesthetic compared to the full mophead.
Hydrangeas with Standout Foliage and Stems
The oakleaf hydrangea, Hydrangea quercifolia, distinguishes itself through its remarkable foliage and bark, offering multi-season interest. Its most defining characteristic is its large, deeply lobed leaves, which resemble the leaves of an oak tree. These deep green leaves provide a lush backdrop throughout the summer months.
As autumn arrives, the foliage transforms, developing rich burgundy-red to mahogany hues, adding dramatic color to the fall landscape. Beyond the leaves, the mature stems exfoliate, revealing peeling, cinnamon-colored bark that provides textural interest, particularly during the winter when the plant is deciduous. Cultivars like ‘Ruby Slippers’ exemplify these traits, offering a compact form with white flowers that mature to a deep rose, alongside the characteristic fall foliage and exfoliating bark.
Unusual Growth Habits and Blooming Traits
Some hydrangeas exhibit distinctive growth habits, departing from the typical shrub form. Climbing hydrangeas (Hydrangea anomala petiolaris) are their vining nature, allowing them to ascend vertical surfaces. They achieve this by developing specialized aerial rootlets along their stems, which enable them to cling securely to walls, fences, arbors, or tree trunks. This vigorous deciduous vine produces flattened, lacecap-like clusters of delicate white flowers in summer, creating a lush, flowering facade.
Another unusual trait involves the plant’s blooming cycle, as seen in reblooming, or remontant, hydrangeas. Unlike many traditional hydrangeas that bloom only on “old wood” (stems from the previous year’s growth), reblooming varieties produce flowers on both old and “new wood” (the current season’s growth). This dual-blooming capability significantly extends their flowering period, from late spring through to late summer or fall. The ‘Endless Summer’ collection is a prime example of this innovation, providing a continuous display of blooms.