Slender vervain Polaris - Verbena rigida f. lilacina

Slender vervain or Verbena rigida f. lilacina Polaris is an undemanding perennial plant that is also heavy blooming and drought resistant. This cousin of purple top verbena enjoys the same growing conditions, but differs with its pale lilac to mauve flowering colour and its more compact, bushy growth habit. It blooms from summer to autumn in sunny flower boxes, flowerbeds and rock gardens. For it to overwinter successfully, it should be planted in well-drained soil, cut down at the end of autumn and provided with a thick, dry mulch to protect it from heavy frost.

Native to South America, more particularly Northeastern Argentina and the pampas of Brazil, Verbena rigida, or slender vervain, is a species that is well adapted to dry climates in the summer and to coastal sites, swept by sea spray. It belongs to the family Verbenaceae. It is a perennial plant with fleshy roots and very rapid growth, allowing it to reach its adult size in a few months. Its growth habit is bushy and well-branched from the base, forming a clump measuring 50 to 60 cm high and 35 cm wide. Its flowering period is very long and lasts from June to October. The flowers of the Polaris cultivar are bright, luminous and gathered in flattened corymbs of a slightly bluish mauve hue, and are carried by stiff, square, branched stems. The foliage is made up of narrow, toothed leaves that are rough to the tough.

It thrives in the sun, in light, well-drained, even stony soils. Moderately hardy (up to -10°), its life span is quite short. If the soil is well suited, this shortcoming will be largely compensated by its ability to ensure its survival by spontaneously self-seeding itself wherever it wishes without becoming invasive. It is a nectar-rich plant that will appeal greatly to butterflies. This variety is still little known but its ease of cultivation and its attractiveness make it a perfect addition to gardens. It is marvellous in seaside or dry gardens, where it can be planted with ornamental grasses, shrubby sages, or in groups with California Poppy, Montbretia or golden Hummingbird Mint, creating a captivating yet modern setting. It can be grown in pots provided that they are well-watered in summer.