A number of the family are hardy perennial border plants. The flowers of most of the species expand in the evening.
O. macrocarpa. - This showy species has large, fleshy roots, which throw out decumbent stems, producing in succession, through the summer, numerous large yellow flowers, four or five inches in diameter.
O. speciosa has creeping roots, with stems one and a half foot high, with large white flowers, from June to September.
O.fruticosa has rather shrubby stems two feet high, with dark yellow flowers in July and August.
O. fraseri is one and a half foot high, with yellow flowers, from June to October.
O. taraxiciflora is a magnificent perennial, not very common, with large white flowers. All the species succeed well in any common garden soil, and easily propagated from divisions of the root, and from seed when it can be obtained.