Plant Profile: Snow-in-Summer (Cerastium tomentosum)

Native to southern Italy, this  short-lived perennial is a member of the carnation family, Caryophyllaceae, that also includes pinks, baby’s breath, and chickweed. The spreading plants form  mats of densely hairy, silvery-grey stems and leaves up to 6″ tall.   The leaves are lanceolate, up to 1″ long, and  evergreen. In early summer, clusters of up to 15 white flowers appear on wiry stems 8-12″ tall.  The star-like flowers  are up to 1″ across and have 5  deeply notched petals.  Snow-in-summer is drought resistant but does best in areas with cool dry summers.  It spreads by self-seeding and underground runners and can become invasive but is useful as a groundcover, edging, and xeriscape, as well as in rock, wall, and cottage gardens.  The genus name, Cerastium, comes from he Greek word kerastes, meaning horned, and refers to the horned seed capsule of some species.  The specific epithet, tomentosum, is the Latin word for densely woolly, with matted hairs, and refers to the stems and leaves.