Mountain Hydrangea, scientifically known as Hydrangea serrata, is a captivating and versatile deciduous shrub native to the mountainous regions of Korea and Japan. This species has gained popularity for its lacecap or mophead inflorescences, foliage, and adaptability. Mountain Hydrangea is closely related to the more well-known Bigleaf Hydrangea (Hydrangea macrophylla). Its botanical name, Hydrangea serrata, refers to the serrated edges of its leaves, adding an extra layer of texture to its overall appeal.
Growing & Caring For Mountain Hydrangea
Mountain Hydrangea performs best in partial shade to filtered sunlight. While it can tolerate some morning sun, protecting from the intense afternoon sun ensures that the foliage remains healthy and vibrant. In regions with cooler climates, Mountain Hydrangea can tolerate more sunlight, but in warmer areas, afternoon shade is beneficial.
Well-drained, humus-rich soil is ideal for Mountain Hydrangea. Amending the soil with organic matter, such as compost or well-rotted manure, enhances fertility and moisture retention. This hydrangea species prefers slightly acidic to neutral soil pH. Regularly testing and adjusting the soil pH can influence the color of the blooms, with more acidic soils promoting blue flowers and more alkaline soils encouraging pink blooms.
Consistent moisture is essential for Mountain Hydrangea, especially during dry spells. Regular watering ensures the plant remains hydrated and supports the development of healthy foliage and abundant blooms. Mulching around the base of the shrub helps retain soil moisture, regulates temperature, and suppresses weeds. Adequate water is particularly crucial during the flowering season and hot summer months to prevent stress on the plant.
Pruning is generally minimal, as these shrubs have a naturally appealing form. However, light pruning can be done in late winter to early spring to remove dead or weak wood and shape the shrub to maintain its desired structure. Since Mountain Hydrangea blooms on old wood, excessive pruning should be avoided to ensure the development of flower buds and a robust floral display.
Popular Varieties of Mountain Hydrangea
‘Bluebird’ is a popular lacecap variety known for its blue flowers and compact growth habit. ‘Preziosa’ features unique color-changing blooms that transition from pink to deep red. ‘Tuff Stuff’ is a reliable and compact cultivar with lacecap blooms, making it suitable for smaller gardens or container planting. Tuff Stuff Hydrangeas bloom either pink or blue depending on the pH of the soil.
Size and Shape:
Mountain Hydrangea typically reaches 3 to 6 feet in height, creating a compact and rounded form. Its growth habit is well-branched, and the shrub tends to maintain a neat appearance. The smaller stature of Mountain Hydrangea makes it suitable for various garden settings, including smaller landscapes, container gardening, and mixed borders.
Leaves and Flowers:
The foliage of Mountain Hydrangea is one of its distinctive features. The leaves are serrated along the edges, providing an ornate texture to the shrub. The leaves can vary from deep green to shades of burgundy in some varieties. The fall foliage often exhibits rich autumnal hues, adding to the overall seasonal interest.
However, the real showstopper of Mountain Hydrangea is its delicate and intricate flowers. The inflorescences come in two main types: lacecap and mophead. Lacecap varieties feature flattened flower heads with small, fertile flowers in the center surrounded by larger, showy, sterile flowers resembling a lacy doily. Mophead varieties, on the other hand, have dense, rounded clusters of large pure flowers that create a more substantial and bold display. The color palette of Mountain Hydrangea blooms includes shades of blue, pink, lavender, and white, depending on soil pH and the presence of specific compounds in the soil.
Uses in the Garden:
Mountain Hydrangea is a versatile and valuable addition to garden designs, offering a range of uses in various settings. Its compact form suits smaller gardens, urban landscapes, or container gardening. Planted as a specimen shrub, Mountain Hydrangea becomes a focal point, captivating onlookers with its intricate blooms and textured foliage. Its adaptability to different light conditions allows it to thrive in mixed borders, woodland gardens, or shaded areas, providing a dynamic and colorful presence.
One of the unique features of Mountain Hydrangea is its suitability for informal hedges or group plantings. When planted in multiples, these shrubs create a cohesive and charming display, especially when different cultivars are selected to showcase a range of colors and flower forms. The lacecap and mophead varieties can be strategically combined to add visual interest and diversity to garden compositions.