Definition of Perennial plant

A perennial plant or perennial (Latin per, "through", annum, "year") is a plant that lives for more than two years. Perennial plants are divided into two large groups, those that are woody and those that are herbaceous. All woody plants are perennials since they form woody tissue that persists from one year to the next. Woody perennials develop a woody base or root system from which the foliage and flower stems grow year after year while the plant is alive. In common usage the term perennial generally describes herbaceous perennials. Since herbaceous plants as a group include all non woody plants, they can be annual, biennial and/or perennial. Perennial plants can be short-lived (only a few years) or they can be long-lived, as some woody plants, such as trees, have been living for over 3,000 years. They can vary in size from only a few millimeters to over 100 meters tall. They include a wide assortment of plant groups from ferns and liverworts to the highly diverse flowering plants like Orchids and Grasses.