The Indian Ocean is the third largest ocean in the world after the Atlantic and the Pacific. It is encircled by Africa, the Southern Ocean, Asia and Australia and is home to a number of endangered marine animals, such as the dugong seals, turtles and whales. The Indian Ocean is considered a tropical ocean, and the plants and animals that live in it play a major role in regulating global climate.

Seagrass is a common plant in the Indian Ocean. Eelgrass, for instance, is commonly found in shallow ocean bays, coves and tidal creeks. It is an important habitat, nursery ground and food source for scallops, crabs and a number of species of fish. The ribbon-like grassblades are long and covered with small marine animals and plants. Eelgrass is also referred to as tapegrass or wild celery, and grows from a dense rhizome system. The heavy growth of the grass discourages the growth of other plants within its colony.

Phytoplankton are an important plant group found in all oceans, including the Indian Ocean. This category of plants includes various species of the microscopic, floating and drifting plants of the ocean. The presence of phytoplankton in the ocean is several times greater than that of land plants and they constitute the start of the food chain. The majority of the plants within this group multiply vegetatively by cell division or formation of spores. Phytoplankton are important as they help to regulate the atmosphere and the overall health of the oceans by absorbing carbon dioxide.

Seaweeds are the large, more visible plants in the Indian Ocean and are considered an important resource of the sea. Seaweeds grow on coral, rocks and other submerged strata in the shallow tidal zones of the sea, providing home and food for sea animals. Seaweeds, with their simple structure and lack of complex roots, absorb nutrients directly from the water. Kelp are an example of large seaweeds that have root-like structures known as holdfasts that help them attach to rocks. A number of other seaweed species grows as they drift on the surface of the sea.