Juncus is a genus of monocotyledonous perennial flowering plants, commonly known as rushes. It is the largest genus in the family Juncaceae, containing around 300 species. Rushes of the genus Juncus are herbaceous plants that superficially resemble grasses or sedges. Juncus has a cosmopolitan distribution, with species found throughout the world, with the exception of Antarctica. They typically grow in cold of wet habitats, and in the tropics, are most common in montane environments.

Juncus effusus ‘Spiralis’, the corkscrew rush, sometimes referred to as Juncus spiralis, is a perennial plant with green spiraling stems. It is a cultivar of the soft rush, Juncus effusus. Plants grow to 45 cm high. The young, leafless stems are light green and coiled, the coils becoming looser with age. Plants grow in both a horizontal and vertical direction. By winter, stems become a yellow-brown or tan colour. Flowers are both rare and insignificant in terms of the plants appearance. They are yellow-green or light brown. The origin of the cultivar is uncertain, though Japan is thought to be a possibility. The cultivar has also been referred to as Juncus effusus f. spiralis and Scirpus lacustris ‘Spiralis’. This cultivar is often confused with Juncus balticus ‘Spiralis’. The cultivar is often grown as a curiosity plant due to its unusual form. It prefers a situation in sun or partial shade and acidic soil. Plants require permanent water, ideally between 5 and 10 cm deep, or continual irrigation. In open soil containers are sometimes used to contain its spread. This cultivar is relatively free of pests or diseases, but is susceptible to drought stress. Plants are maintained by the removal of old stems in spring. It is suited to container cultivation and can be used as an indoor plant. It can be grown on the edge of water bodies to help control erosion. Propagation is through seed or by division of plants during the active growing phase of the plant. Stems are used in floral arrangements along with cut flowers. It can self-seed and become troublesome in some areas.