Flowering perennials : characteristics and culture
Flowering perennials represent a large group of garden plants with roots that persist from year to year. Stems and leaves of some may remain, but in most, the tops die back to the soil each winter. Perennials are suitable for many locations. Most frequently, they are incorporated in a flower border that they share with annual flowers and shrubs. Perennials with similar cultural requirements are grouped into plantings known as rock gardens, wildflower gardens, bog gardens or perennial flower borders.
Archive version. For the most recent information see extension.missouri.edu.