Hydrangea macrophylla Soeur Thérèse

The 'Sœur Thérèse' Hydrangea macrophylla is a unique and delicate variety of hydrangea that dates back to 1944. It has excellent floribundity and produces rounded, light flower heads with cool, white-coloured florets with a small blue heart. The flowers gradually turn red in late summer before taking on a mysterious watery green hue in autumn, adding a mystical charm to the place. The plant has magnificent dark green and bluish foliage that adorns a slightly spread-out tall bush supported by graceful but robust stems. It thrives best in shaded, cool exposure and non-chalky soil to reveal its true beauty.

The Hydrangea macrophylla Soeur Thérèse, also known as "Petite soeur Thérèse de l'enfant Jésus," was created in Paris. Often confused with the famous 'Mme E. Mouillère' variety by Victor Lemoine, Soeur Thérèse's flower is whiter, its foliage less serrated, and its stems thicker and more sturdy. Soeur Thérèse results from cross-breeding between the H. macrophylla and H. aspera species. All of these hardy plants belong to the Hydrangea family, which is native to China and Japan.

Soeur Thérèse has a rather spread out and full habit, regular and slightly arched. When mature, it reaches around 1.50 m (4 ft 11 in) in height with a spread of 1.70 m (5 ft 7 in). From July to September, its small fertile and sterile flowers, with striking dimorphism, form round flower heads measuring 16 to 18 cm (7.1 in) in diameter that are loose, with visible petioles. They form pure white sterile florets when they bloom, the colour of which evolves if the plant is sufficiently shaded. The flowering extends over foliage that looks very healthy, with a dark bluish-green colour, rather matte.

The leaves are opposite, reaching a minimum length of about twenty centimetres. They are simple, ovate to elliptical, ending in a tapered point and coarsely serrated like a saw. Hydrangeas can live for at least 50 years.

The Soeur Thérèse Hydrangea is a beautiful and intriguing plant with a delicate appearance and perfect for growing in semi-shade. Hydrangeas are well known for their ability to brighten up the north side of houses, and this particular variety will thrive in areas with an east or north-facing exposure where it can avoid the scorching summer sun. These plants can be used in shrub beds and hedges, and they add a lot of charm to areas of the garden that are a bit darker or near a concealed entrance.

Although Soeur Thérèse Hydrangeas do not like limestone, they are not strictly acid-loving plants. You can pair them with Magellan fuchsias, annual impatiens, or plant spring-flowering bulbs in front of their rounded silhouette. You can enjoy their sumptuous and long-lasting flowering in the garden or bring them inside the house.