Ornamental grass

Ornamental grasses are grasses grown as ornamental plants. They have become increasingly popular in gardens in recent years.

Along with true grasses (Poaceae), several other families of grass-like plants are typically marketed as ornamental grasses. These include the sedges (Cyperaceae), rushes (Juncaceae), restios (Restionaceae), and cat-tails (Typhaceae). All are monocotyledons, typically with narrow leaves and parallel veins. Most are herbaceous perennials, though many are evergreen and some develop woody tissues. They bring striking linear form, texture, color, motion, and sound to the garden, throughout the year.

Almost all ornamental grasses are perennials, coming up in spring, from their roots, which have stored large quantities of energy, and in fall or winter go dormant. Some, notably bamboos, are evergreen, and a few are annuals. Many are bunch grasses and tussock grasses, though others form extensive systems of many-branched rhizomes. The bunching types are often called "clump-forming" or "clumping", distinct from the rhizomatous types, called "running". Sizes vary from a few centimeters up to several meters; the larger bamboos may reach 20 m or more tall. Some ornamental grasses are species that can be grown from seed. Many others are cultivars, and must be propagated by vegetative propagation of an existing plant.

...
Wikipedia