On the basis of growing, there are three types of plants:-
Annuals, Biennials and Perennials
The difference between annuals, biennials and perennials can be confusion to the new or beginner gardeners, especially when the issue of winter, hardiness (cold toleration) comes to play main role in the northern part of the earth because northern parts are colder than mid parts (tropical, subtropical) of the earth. The following explanation might be helpful to make clear from this confusion.
One of the main differences between annuals, biennials and perennials is that an annual is classified as a plant that completes its growth cycle in one season/year. Propagation of annual plant is performed mostly by seeds, but tips or branches also can be used of some plants to produce a new plant. When annual flowers are cut or pinched off, the plant will respond by forming more sub branches, bear lots of buds and blooms to assure that there will be seeds for the next year’s crop (or for the next generation). Because of need to produce seeds, annuals generally grow faster, bloom earlier and produce more flowers and seeds than perennials. Some plants that are treated as annuals in the north (because of cold climate which is also called ‘northern climate’) are actually perennials in warmer climates (tropical, subtropical), such as: geranium, salvia, portulaca, dianthus, daises, cana lily, hosta, fern etc.
Some examples of true annuals are: Pansy, Petunia, Sweet pea, Verbena, Vinca, Jalapa, Cypress vine, Morning glory, Coleus, Zinnia, Cosmos, Nasturtiums, Marigold etc.
Biennials are plants that have two years growing cycle and they can live two years or longer. The plants grow roots and foliage the first year and flower and seed the second year for the next generation. Biennials are usually purchased as second year plants from nurseries. Most characters of annuals and biennials are similar. Biennial propagation is also performed mostly by seeds and tips or branches also can be used of some plants to produce a new plant. Usually, new gardener may confuse between annual and biennial plants.
Some examples of true biennials are: Foxglove, Sweet-william, Hollyhocks, Dianthus etc.
Perennial plants can live three years or longer, some will last indefinitely, some won’t. They have roots that live through the winter (even too cold) and they may or may not die back in the winter. Some perennials can bloom throughout the growing season (during warm temperature- Spring, Summer and Fall), if the blooms and seeds’ pods are removed after flower faded) but some won’t. Perennials can be started from seed too, but mostly they are propagated by dividing or by taking cuttings because they take long time to mature growing by seeds. Perennials are often used in concert with annuals to provide contrasts and blooms during different parts of the growing season. Mostly trees, large vines, shrubs are fall in perennial plants.
Some examples of true perennials are: Rose, Oleander, Hydrangea, Paper Flower, Rubber Plant, Different Cactus and Succulents, Azalea, Honey-Suckle, Malati etc.