Plant of the Week: Pentaglottis Sempervirens

By Davis Landscape Architecture @DavisLandArch

Pentaglottis sempervirens Flower (14/04/2012, London)

Position: Full sun to partial shade

Flowering period: Spring to early summer

Soil: Moist, well drained

Eventual Height: 90 cm

Eventual Spread: 60 cm

Hardiness: 7a – 9b

Family:  Boraginaceae

Pentaglottis sempervirens is an evergreen herbaceous perennial. Its dark green leaves are sessile, acuminate with an entire margin, rough and hairy and deeply veined. Its deep blue to violet hermaphrodite flowers are up to 1cm in diameter, have five petals, with stamens that are hidden inside narrow flower tubes which end in a white eye in the center of the flower. The plant produces deep tap roots from which the plant readily re-grows making it hard to eradicate once established.

Pentaglottis sempervirens (14/04/2012, London)

Pentaglottis sempervirens, commonly known as Evergreen Bugloss, Green Alkanet or Alkanet, is native to south west Europe and is not native to the UK. It was introduced into the UK for the red dye which can be extracted from its roots. It has become widely naturalised in hedgerows, woodlands, roadsides, shady places and waste ground, usually on poor sandy or stony soils in southern England. Its flowers are edible.

The etymological root of the binomial name Pentaglottis is derived from the Greek meaning ‘five tongues’. Sempevirens is from the Latin meaning ‘always green’.

Pentaglottis sempervirens Detail (14/04/2012, London)

The landscape architect may find Pentaglottis sempervirens useful for specifying in damp shady locations. Once established this plant may be difficult to eradicate.

Ecologically, P. sempervirens is attractive to pollinating insects.

P. sempervirens prefers moist, fertile, well-drained soils. It prefers a neutral to alkali pH of soil.

P. sempervirens requires little maintenance.