Perennials return year upon year and are the mainstay of most gardens. They come in varied shapes and sizes.
Perennials die back in the winter and then regrow in the spring. Evergreens keep their leaves during the winter months and flower during the summer. Ground cover plants are low growing perennials. Half hardy perennials need a little extra attention of a layer of thick mulch (fallen leaves, grass cuttings, bark, etc...) to see them through the frosts.