Perennial knawel - Scleranthus perennis

''Scleranthus perennis'', the perennial knawel, is a perennial herbaceous plant of the carnation family. It grows on sandy, dry, acidic soils. It can grow up to 15 cm high and has white flowers of 2–5 mm. The plant used to be economically significant as the major host plant of the Polish cochineal.