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Perennial plant
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Perennial plant

   

, a perennial plant.]] A perennial plant or perennial (Latin per, "through", annus, "year") is a plant that lives for more than two years. This term is usually applied to herbaceous plants or small shrubs rather than large shrubs or trees, but used strictly it also applies to the larger and longer-lived species. As opposed to annual plants, which never flower again after withering, or biennial plants, which only live for two seasons, perennials can come back season after season.

Just because a plant is classified as a perennial doesn't mean the one you've planted in your garden will come back next year, depending on its climate ("zone") hardiness. Zones are geographic areas of climate where conditions are favorable for particular types of plants. In North America, the farther north you live the lower your zone number will be. If you live in Zone 4, for example, plant flowers, trees and shrubs that are zoned number 4 or lower. Plants hardy to Zone 5 or higher probably will not reappear in the spring.

Herbaceous perennials are plants that do not form permanent woody tissue. In warmer and more clement climates they may grow continuously. In seasonal climates, their growth pattern is adapted to the growing season. In cooler temperate regions they generally grow and bloom during the warm part of the year, and the foliage dies back every winter. Regrowth is from their existing tissue or root-stock rather than from seed, as with annuals and biennials.

In some cases, these perennials may retain their foliage all year round, even in seasonal climates. Herbaceous perennials that retain their foliage all year round may be called evergreen perennials.

Some perennials are called evergreens, because the keep their leaves between seasons. Others are called deciduous.

Examples of evergreen perennials; Begonia; banana

Examples of deciduous perennials; Goldenrod; mint

Woody perennials (ie.trees and shrubs) retain their woody structure permanently, but may lose their foliage in seasonal climates.

Perennial plants dominate most natural ecosystems. For example, grasses and most forbs on the prairie are perennial. Wild perennial plants are usually better competitors than annual plants, especially under resource-poor conditions. This is due to larger root systems which can access water and soil nutrients deeper in the soil and to earlier emergence.

There are many perennial plants important to human food production including most fruit and nut trees.

See also: annual plant, biennial plant

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