Aquatic umbrella plants are named for the arching shape of their leaves, which resemble open umbrellas. Often incorrectly classified as Cyperus alternifolius, the correct botanical name for these plants is Cyperus involucratus, according to the University of Florida. These plants, which are native to Africa and were brought as ornamental plants to the United States, have become naturalized in many boggy areas of the southern United States.
Cyperus involucratus (alternifolius) can grow to heights of 5 feet if kept properly watered, according to the University of Oklahoma's website. The long, slender stems grow from clumps of rhizomes and are topped with a cluster of elongated, thin leaves arranged in a pinwheel shape. There are about 24 of these leaves that form the "umbrella" (or pinwheel). In the center of the "umbrella" are groups of small, light-green flowers that bloom in the spring.
These plants are classified as tender perennials. This means that they will not survive year-round in climates with freezing winter temperatures. C. involucratus grows best in USDA hardiness zones 8 to 11. While freezes may kill the foliage, the plant will bloom again in the spring if the rhizomes are not frozen. In colder climates, the plant can be grown in a container and brought indoors for the winter, or even be grown indoors year-round.
Aquatic umbrella plants thrive in very wet, cool areas. They can grow in part shade or even full shade, according to the Missouri Botanical Gardens, making these plants an excellent choice for planting under trees. Too much sun will scorch the leaves of the plant. C. involucratus can also grow in standing water as deep as 4 inches.
Cypres involucratus (alternifolius) can be planted along the wet borders of ponds, bogs or lakes. The plant grows well in containers and makes a nice specimen plant when placed on the edge of a water feature. This versatile plant can be grown in any home garden if given plenty of water.
Aquatic umbrella plants are easily propagated, according to the Floridata website. Dig them up and divide the clumps of rhizomes, or simply cut a stalk and insert it into rich, sandy soil. The individual stems will take root if kept in a sunny location and if the planting medium is kept continually moist.