Juncus is a large genus of annual and perennial plants in the Juncaceae family. It has a widespread and cosmopolitan distribution, with these plants being found in all parts of the world except Antarctica. There are over 300 recognised species, usually found in cold, wet habitats. When in tropical regions, they are found in the cooler montane areas. Commonly known as Rushes, they have clumps of narrow or cylindrical leaves and clusters of small brown flowers along the leaf-like stems. In cultivation, they are usually grown in boggy areas or at pond margins. Cultivars with twisted or variegated stems (such as Juncus effusus f. spiralis) are interesting and popular ornamental forms.