Carex is the scientific name of a genus of perennial, grass-like plants commonly called sedges, and often referred to as "true sedges" to differentiate them from similar plants that do not belong to the Carex genus. Different species of sedge are part of the native vegetation almost all over the world, including North America, Asia and Europe. In the wild, these plants usually prefer moist growing conditions, for example along lakes and streams or in bogs and marshes. Sedges vary in size and appearance, but share some similar characteristics: they are usually evergreen, they form clumps as they grow, and their foliage is thin and blade-shaped, similar to ornamental grasses. Many species in the Carex genus are commonly grown as garden plants, and are prized because they are easy to care for, usually drought-tolerant once established, and can grow well in both sun and deep shade.
The Carex genus of plants has been extensively studied by botanists ever since 1753, when the famous Swedish botanist Carl Linnaeus named and described it in his groundbreaking botanical work "Species Plantarum" ("The Species of Plants"). The branch of botany devoted to the study of the Carex genus is called caricology. It is estimated that more than 1,000 species belong to this genus, and while many kinds are still common in their natural habitats, others are threatened with extinction.
Some species of sedge grow only a few inches high, while others can grow several feet tall. The foliage also varies with the species, and is commonly green, golden, yellow, rust-colored, or variegated in white and green. In gardens, true sedges can be used for a variety of purposes, such as along pathways, under trees, or around garden ponds. Some of the lower-growing varieties, for example Carex divulsa, also known as Berkeley sedge, can be used as ground-coverage instead of grasses, either in shady or sunny locations. Taller varieties with more striking foliage like Carex elata "Aurea," also known as Bowles' golden sedge, can be used as ornamental plants in areas with deep shade.
Sedges are often used as landscaping plants in settings where sustainable landscaping is desired. Many plants in the Carex genus tolerate drought well once they are established, making them a good choice to replace plants that require frequent watering. Sedges are also used when restoring wild habitats, for example along rivers or in wetland areas. In the wild, many species of the true sedges provide both food and habitat for wildlife.