Hydrangea macrophylla

Hydrangea macrophylla is a species of flowering shrub in the hydrangea family, Hydrangeaceae.

Hydrangea macrophylla is a species of flowering shrub in the hydrangea family, Hydrangeaceae. It is native to Japan and is widely cultivated as an ornamental plant for its large flower clusters, which are often pink or blue depending on soil conditions. It is commonly known as bigleaf hydrangea, French hydrangea, or hortensia.

Description

Hydrangea macrophylla is a deciduous shrub growing up to about 3 m tall. It has broad, serrated leaves and produces large flower clusters in summer and autumn. Cultivated forms are often grouped as mophead or lacecap hydrangeas, referring to the rounded or flattened shape of the flower heads.

Distribution and habitat

The species is native and endemic to Japan. Its natural range includes coastal habitats of Honshu southwards and in southern central Japan, including nearby islands. It has been widely introduced and cultivated in many regions around the world.

Cultivation

Hydrangea macrophylla is grown internationally as an ornamental garden plant, valued for its large flower heads and long blooming season. Cultivated plants are often selected for flower form, size, and colour. In Canada, it is widely grown in gardens and nurseries, particularly in milder regions and sheltered locations.

Flower colour

Flower colour in cultivated Hydrangea macrophylla can vary between pink, blue, lavender, and sometimes white. The shift from blue to pink is commonly associated with soil pH and related nutrient availability, with acidic soils often producing blue flowers and alkaline soils producing pink.