What is the Difference Between Annual and Perennial Plants?

The difference between annual and perennial plants is simple: annual plants complete their life cycle within a year, while perennial plants live for over two years. A third classification, biennial plants, refers to plants with a two-year life cycle. Annual plants may have a life cycle of any duration under a year; some have life cycles of only a few weeks. Perennials may live for just a few years or for well over 20 depending upon the species of plant. Annual plants that naturally complete their life cycle in under a year are known as true annuals, but some biennials and perennials may be grown as annual plants in certain contexts. For example, some annual plants may be perennial in their native habitat, but are not hardy enough to survive winter in the environment in which they are grown. Certain root vegetables, such as carrots, are biennials that are treated as annual plants, harvested in their first year for the strong root that grows to provide nourishment to the plant in the ...  more

Annuals will bloom over a longer period but last one growing season and perennials will come back year after year.