You’ve probably heard the terms annual, biennial and perennial used in the description of plants. Even with plant descriptions on this website, we use these terms. So what exactly do they mean?
Annual plants completes their life cycle, from germination to the production of seeds, within one year, and then dies. They are generally smaller plants and can be broken into into summer annuals which sprout, flower, produce seed, and die, during the warmer months of the year. And winter annuals germinate in autumn or winter, live through the winter, then flower in late winter or spring. Some Utricularia are annual plants, returning each year from seed.
Biennial plants are flowering plants which take two years to complete their life-cycle In the first year, the plant grows leaves, stems, and roots before it enters a period of dormancy over the colder months. Usually the stem remains very short and the leaves are low to the ground, forming a rosette. Many biennials require a cold treatment before they will flower. During the next spring or summer, the stem of the biennial plant grows. The plant then flowers, producing fruits and seeds before it finally dies. There are far fewer biennials than either perennial plants or annual plants. There are some Drosera which some growers consider biennial, depending on where they are grown.
perennial plants or simply perennials are plants that lives more than two years. The term is also widely used to distinguish plants with little or no woody growth from trees and shrubs, which are also technically perennials.
Perennials, especially small flowering plants which grow and flower over the spring and summer, die back every autumn and winter, and then return in the spring from their root stock, are known as herbaceous perennials. Most carnivorous plants, including Dionaea muscipula, are herbaceous perennials.
Plants can behave and grow differently when cultivated outside of their natural climate. Some plants grown in climates colder than their natural climate may grow as annuals, while in their original climate may be biennial or even perennial.