Ceratostigma willmottianum

The Ceratostigma willmottianum, also known as Willmott's Plumbago, is a late-flowering bush that is interesting for its magnificent autumn colours, as well as its low requirements for soil and watering. Its small blue flowers bloom on a bronze-green foliage that becomes dazzling at the end of the season, creating a stunning colour combination. In well-drained soil, the plant can withstand brief frosts of around -14 °C.

The Ceratostigma willmottianum, sometimes called Leadwort or Willmott's Plumbago, belongs to the Plumbaginaceae family. It is a deciduous shrub native to western China and Tibet that thrives in sun and warmth, as well as in draining, chalky soils. Its honourable hardiness depends on the humidity of the soil in winter. It is a slightly suckering shrub, with a flexible habit and somewhat loose, spreading growth, reaching around 1 m (3 ft 4 in) in height and 1.50 m (4 ft 11 in) in width.

Its growth is quite fast. The foliage is deciduous, falling in late autumn and reappearing quite late in spring. The small leaves have an oval shape that approaches that of a diamond and are covered with fine hairs on the top and bottom. Their colour changes from medium green in spring to bronze-green to yellowish-green in summer, then turns red from September onwards. From July until the frosts, it produces a myriad of tubular flowers with 5 petals, of a particularly vibrant blue. In autumn, the foliage, which has turned purple-red, combines perfectly with the blue flowers.

This Willmott's Plumbago is an excellent plant for flower beds. It will thrive in most areas, except for the cold and dry ones in summer. In the garden, plant it with yellow flowers (Coreopsis Sunray, goldenrods, heleniums) or with white, mauve, and pink asters. Pink groundcover roses with slightly blurred shapes like The Fairy, Mareva, or Emera will also look beautiful, along a path or in front of taller bushes. Companion planting with fuchsia, orange, or red flowering shrubby salvias is gorgeous. If bright colours are not your thing, pair them with a Powis Castle artemisia to calm down this colourful composition!