Dense vigorous multi-stemmed shrub with lush light-green leaves, bold and saucer-shaped. In summer large clusters of intense blue or pink flowers on unusual purplish-black stems which contrast well with the flowers and foliage. Flower colour can vary from blue to pink depending on soil acidity. The flowers form on two year old wood. Thin out crowded stems in late winter, shorten where necessary. Hardy for cold sites. Best in semi-shade, with good soil moisture.