What Does Perennial Species Mean?
Perennial species are a category of plant life that live for more than two years and can live indefinitely for many years in some species. This is contrasted with the other types of plant; annual and biennial, which have shorter life spans. Annual species live for only a single growing season, during which they produce seeds and then die. Biennial species live for two growing seasons.
Safeopedia Explains Perennial Species
All trees and shrubs are technically classed as perennial plants, but horticulturalists often make a distinction between woody plants and herbaceous plants. The woody plants have above ground parts which persist through winter and then resume growth in spring. Herbaceous perennials lose their above ground growth over winter with only their root system surviving, and regrowth occurs in the spring.