Hydrangea serrata Blue Bird - Mountain Hydrangea

Hydrangea serrata 'Bluebird' offers a particularly charming flowering and beautiful hardiness. Its corymbs appear from the beginning of summer and continue until autumn. In addition to their lovely shades, between pink and blue, they are also adorned with a crown of lace, formed by four-petaled flowers that surround a multitude of small buds in the centre. Its compact habit and dense foliage allow for a beautiful volume of one cubic metre, which will fill semi-shaded spaces in moist soils.

Originating from the mountains of Japan, Hydrangea serrata is robust, resistant, and not very frost-sensitive. It thrives in rainy, cool climates with little sun. Preferring partially or significantly shaded exposures, it will tolerate the sun if its roots remain cool. It appreciates acidic to neutral soils, preferably rich and humus-rich.

It has numerous ramified stems forming a rounded bush that can reach up to 1.2 m (3.9 ft) in height and spread over 1 m (3.3 ft) in width. Its deciduous foliage is dense and creates a beautiful backdrop for perennials placed in front of it. It consists of dark green, lanceolate leaves with dentate margins (hence the serrulate qualifier), marked by beautiful veins that are noticeably lighter. These leaves tend to turn red in the sun and become plum or violet. Above this ensemble, the flattened corymbs succeed each other throughout the summer, revealing subtle nuances between pink and blue, sometimes even starting from white and turning violet. These changing tones, depending on the nature of the soil, allow for varied pleasures in different gardens or even locations, thus bringing beautiful surprises. The effect is accentuated by the presence of two types of flowers. In the centre, multiple fertile flowers remain in tight buds. On the periphery, the sterile flowers, consisting of four petals arranged in a cross, emphasise this little dome with a pretty skirt. The contrast between the two is maintained by different shades: the periphery is often lighter than the centre.

'Bluebird' is not invasive and easily finds its place at the foot of a bare and poorly exposed wall. It also borders entrances and pathways and creates fluffy ensembles with all its cousins. Vary the sizes, colours, and flowers by choosing companions such as quercifolia or macrophylla. At the base, shade-loving perennials will complete the picture in blue tones: Brunneras, perennial Geraniums, or Heucheras to contrast with their colourful foliage.