Caryophyllaceae. Indigenous perennial in Europe and temperate Asia, widely spread throughout France. It is closely linked to wet environments — marshy meadows, ditch edges, lowland and mountain bogs, tall herb communities — where it can form dense and spectacular populations as evidenced by the third view, a true pink carpet extending over dozens of meters.
The erect stems, slightly sticky to the touch, reach 30 to 60 cm. The foliage is narrow, lanceolate, medium green, arranged in opposite pairs along stems often tinged with reddish-brown. The calyxes are streaked with well-visible purple veins.
The most distinctive feature of the species lies in its petals deeply cut into four narrow and irregular strips, giving each flower a fringed and slightly disordered appearance, from delicate lilac pink to bright pink. This floral lace, unique among European lychnis, earns it the popular name "cuckoo flower". In its natural habitat, its flowering extends from April to June.
In cultivation, it requires constantly fresh to moist, rich soil, in full sun or partial shade. It is perfectly suited to wet flower meadows, banks, and natural gardens where it readily reseeds itself.