- Latin synonym: Silene flos-cuculi
- Written also: Ragged-robin
- Family: Pink Family – Caryophyllaceae
- Growing form: Perennial herb.
- Height: 30–60 cm (12–25 in.). Stem with sparse, short, quite rough hairs, sticky.
- Flower: Corolla regular (actinomorphic), rose–violet red, 2.5–4 cm (1–1.6 in.) broad; petals 5, deeply 4-lobed. Corona small. Calyx 5-lobed, dark reddish brown-striped. Stamens usually 10. Gynoecium syncarpous, with 5 styles. Inflorescence a lax cyme.
- Leaves: Opposite, basal leaves stalked, stem leaves stalkless. Basal leaf blades narrowly oblanceolate, stem leaves’ narrowly lanceolate–long, with entire margins.
- Fruit: Greenish, 5-valved, 8–13 mm (0.32–0.52 in.) long capsule.
- Habitat: Springs, spring swamps, shores, damp shore meadows, road and field ditches, hay fields.
- Flowering time: June–July.
Ragged robin is to any extent common only in southern Finnish springs, spring swamps and damp meadows. It only grows here and there in central Finland and the northern limit of its habitat is around Tornio. Ragged robin spread with agriculture to grow near people: forest pastures, shores, peatland meadows and open field ditches gave ragged robin many more places to grow in. Changes in agriculture have been fatal, however, and the species has become rare. The plant can’t be missed during its flowering time in early summer, but after it has flowered it can be difficult to find among other meadow vegetation. Stands are often small, but ragged robin areas up to an acre big can still be found here and there. During its flowering time a large stand is probably one of the most thrilling sites in Finnish nature. As a garden plant it has developed into an impressive, abundantly-flowering perennial. Garden varieties have also been developed, some of which are susceptible to the Finnish winter. Ragged robin’s beauty easily attracts insects: hordes of butterflies and bees in particular visit the plant in the early summer, but flower flies are also able to pollinate the flowers.
Ragged robin and sticky catchfly (Silene viscaria) look like each other to such an extent that they are both sometimes grouped into ragged robin’s genus. Both have narrow leaves and rigid and somewhat glabrous stems, whose nodes have sticky undersides. During their flowering times their similarity is not so apparent because the eye is drawn to the plant’s ragged-edged petals. On the other hand, species in the genus that are cultivated as ornamentals, such as Maltese cross (or burning love, dusky salmon, flower of Bristol, Jerusalem cross, etc, L. chalcedonica), which grows on many Finnish yards, does not look anything like it.