Charming deciduous shrub, that grows up to 1.00-1.50 m.
Native of Japan ( Honshu, Shikoku and Kyushu islands) and Korea, where it grows in mountain woods ( from 500m to 1500m above sea level): in Japan these hydrangeas are named ‘yama ajisai’(‘yama’ means mountain, ‘ajisai’ means hydrangea)
Flowering time ranges from June to August.
The leaves can be ovate, lanceolate or elliptic with acute or acuminate tips, more or less pubescent and dull in appereance.
The texture is thin , as opposed to the thicker of H.macrophylla,
The inflorescence is a flat-topped or slightly convex corymb: it can be either a lacecap or a mophead of small-medium size..
H.serrata is a shrub of smaller stature but not less hardy than H.macrophylla: in its native habitats it grows in open places in the cooler north, but in the warmer south it often requires the shelter of woods.
Many cultivars change the flower colour with soil pH; there is one group that never shows a hint of blue, no matter what composition the soil may have: the sterile flowers open white and then in sunlight change through pink to various shades of red.
Hardy to –20°C. It was introduced into Europe around 1843.