Aster alpinus Blue Beauty

Aster alpinus 'Blue Beauty' is a pretty variety of Alpine Aster whose flowers are a very bright light blue. This low-growing, cushion-shaped perennial with a woody base is covered in soft hairs. It flowers from spring to the first half of summer, depending on the region. Fully hardy, simple and undemanding, this little aster thrives in full sun in calcareous and well-drained soils. It is a true gem for rock gardens.

Aster alpinus belongs to the Asteraceae family, and is native to the Alps, where it grows in mid-mountain areas among rocks and pastures. 'Blue Beauty' is a horticultural selection with light blue flowers. This perennial shows a spreading tufted habit from spring, forming dense and compact mats. It will not exceed 20 to 25cm (8 to 10in) in height when in flower, and will spread at least 20cm (8in). Its growth is quite slow, and the lifespan of the plant will be shorter in rich and poorly drained soil. Flowering occurs from April to June-July, depending on the region, and lasts about a month. The inflorescence is a solitary head, 4 to 5cm (2in) wide, with ligulate peripheral flowers that are sky blue in colour. The central flowers (the heart) are yellow marked with brown. This aster is a deciduous to semi-evergreen perennial in winter, depending on the climate. The leaves at the base of the hairy stems are pubescent, rough on both sides, generally entire, elongated, lanceolate, and dark green in colour. They are sessile (without petiole) and acute. The fruit is an achene topped with a dirty white bristle twice as long as the achene. This plant spreads through underground woody stems.

In nature, it is found in warm and calcareous mid-altitude stations, in meadows, in clearings, on forest edges, on slopes, and along paths. We can take inspiration from this in the garden by planting 'Blue Beauty' in sunny rock gardens, alongside Scabiosa columbaria 'Pink Mist' or Sedum 'Red Cauli', emerging from a carpet of delosperma. It is also perfect for creating the junction between perennial borders and pathways, or the top of walls. And of course, it is ideal in rock gardens or alpine troughs, or even in pots.