Greek lychnos—a lamp, referring to the bright flowers.

Annual or perennial herbs. Leaves opposite; stipules absent. Flowers mostly bisexual. Sepals 5, toothed, veins 10. Petals 5 with coronal scales (projections on the upper petal surface towards the base of the petal). Stamens 10. Styles 5; spring to summer flowering. Ovary 1-celled. Fruit a stalked capsule opening with 5 teeth at the top and enclosed by the persistent sepals.

Perennials by division, annuals by seed.

Difficult to distinguish from Silene without ripe fruit. Styles 5, capsule opening with 5 teeth in contrast with Silene which has mostly 3 (rarely 5) styles the teeth being twice the number of the styles. The two genera are clearly extremely similar.

About 15-35 species (depending on the botanical authority) from northern temperate to arctic regions.

This combined key to Silene and Lychnis has been modified from that in European Garden Flora (1st edition) vol. 2 pp. 179-80. The key includes some of the less frequently grown species. Only the commonly grown species are described in the text.

Source: Spencer, R. (1997). Caryophyllaceae. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 2. Flowering plants. Dicotyledons. Part 1. The identification of garden and cultivated plants. University of New South Wales Press.