The Lewisia genus belongs to Portulaceae (the Purslane family), It is a perennial herb that consists of 19 species and occurs around the Rocky Mountains in North America. This herb grows on arid sand and gravel, and the leaves are carnose and form rosette. It bears flowering stalks and bloom pink, white, or orange flowers from spring to summer. The many cultivars have been raised. The 2nd photo is a cultivar 'Susan'. The specific epithet is named after Meriwether Lewis, the 18th-century American explorer.