Hydrangea macrophylla Nikko Blue

The Nikko Blue Hydrangea macrophylla, originating from Nikko in Japan, is an incredibly floriferous and hardy hydrangea perfect for small gardens in cold regions. Its flower clusters bloom from early summer to October, and their colour depends on the soil's acidity. Acidic soil or soil rich in aluminium sulphate will produce a stunning azure blue hue, while neutral soil will result in a charming pastel pink. Though it may take some time to establish itself, this shrub will reward patient gardeners with 3 to 4 months of gorgeous flowers in a semi-shaded garden or terrace area.

The 'Nikko Blue' hydrangea belongs to the Hydrangeae family and is derived from a species of Hydrangea macrophylla native to China and Japan. At maturity, this bushy and well-branched shrub spreads to approximately 1.20 m (3 ft 11 in) in height and 1.50 m (4 ft 11 in) in width. During the summer months, from June to October, its small sterile flowers with 4 petals are clustered on dense, slightly flattened spherical flower heads, which are about 15 cm (5.9 in) in diameter. These flower heads can range from blue to pink and will be light or intense blue if the shrub is grown in acidic soil or soil rich in aluminium sulphate. The flowers are carried by flexible and slender stems aged one year or more. The shrub features beautiful dark green foliage, which is somewhat rounded and takes on yellow or red hues in autumn before falling off. The foliage is opposite on the branches and reaches about ten centimetres in length. The leaves are simple, ovate, ending in a pointed tip and are strongly toothed like a saw. Hydrangeas have a lifespan of at least 50 years.

The 'Hydrangea Nikko Blue' is a versatile plant that can be grown in gardens of all sizes. It can also be used as a beautiful shrub on terraces or balconies. Macrophylla hydrangeas are an essential choice for semi-shaded areas of your garden. Nikko Blue will complement a white hydrangea such as Madame Mouilère, Libelle, or even Great Star Blanc Bleu. While hydrangeas dislike limestone, they are not exclusively suited for heather soil. However, the colour of their flower heads is often influenced by the nature of the soil. Co-planting with magellanica fuchsias, Pieris, Sarcococca, annual impatiens, or spring-flowering bulbs and lilies creates a striking display. You can enjoy their stunning blooms in the garden or bring them inside to place in a vase.

 Please note that the colour of the flowers on macrophylla hydrangeas depends on the soil pH level in which they are planted. Blue varieties of hydrangeas typically turn pink when planted in neutral or alkaline soil. If you want to maintain the blue colour of your hydrangeas, add ericaceous soil or sphagnum moss to your garden soil and add aluminium sulphate (slate contains aluminium sulphate) or alum stone every spring.