Sea Grass Types

The ecosystem relies on hundreds of small plant life, which may seem minute to those who do not live in the water and have gills. One of these plants is seagrass, which provides food and sanctuary for several types of marine life. There are a handful of main seagrass varieties, and they anchor themselves from the sea floor using rhizomes (bulbs) in order to flourish and grow. This in turn makes the water move more slowly throughout the area and also provides more shade from harsh sunlight.

Manatee Grass

Manatee grass needs warm shallow waters to survive, thriving mostly along the eastern Florida coastline to the Gulf of Mexico, along Cuba, Bahamas and the Caribbean Islands in depths of 2 to 3 feet (but it can also survive in waters up to 60 feet deep). With blades ranging from 4 to 10 inches long that are only about .1 an inch wide, this seagrass produces small delicate flowers. Manatee grass grows in thick dense clumps and colonies, and the cylindrical grass has an extensive root system. It also prefers to grow in mud or fine grain sand beds.


At around four feet tall, Eelgrass thrives in shallow areas such as bays and estuaries. This variety grows in several areas, from Greenland to North Carolina, to the Pacific Coast of North America. With thin ribbon-like leaves, the eelgrass rhizomes measure about 1/8 inch long on average. This seagrass provides a home and diet for marine life such as scallops, crabs, sea turtles and fish; and is also a food source for birds like the Canada geese, black ducks and widgeon. It dies back in summer then thriving again once spring and fall come around.

Turtle Grass

Hence the name, turtle grass is a primary food source for green sea turtles. The flat streamer-like blades grow about 1/2 inch wide and grow anywhere from a foot to three feet long and have an extensive root system. Common in the waters around Florida, the Caribbean and as far south as Venezuela, turtle grass thrives at low tide levels. Turtle grass produces white to green to pink flowers and scaly fruits that are round and tough. Ideally, this seagrass likes muddy habitats.

Shoal Grass

This seagrass probably most resembles land grasses out of all the varieties (and also slightly resembles turtle grass). With rigid, flattened blades that range from 1 1/2 inches to a little over one foot long, this notched-tip seagrass thrives in sub tidal zones, particularly mud. It can grow in depths of 40 feet and has been found from around the South America coast, West Africa, the Indian Ocean and North Carolina. In depths of about two feet, it can grow to create large colonies and seagrass fields. Shoal grass ranges from as far north as North Carolina all the way down the coast of South America.

Johnson's Grass

Since 1998 this species has been listed as threatened and mainly thrives in Florida waters. The elliptical pointy blades are about one inch long and .1 inches in diameter. The main feature that distinguishes this variety is the lack of basal sheaths on the sea grass blades. Johnson's seagrass is found most often in shallow waters that are about 6 feet deep, particularly in coastal lagoons or coves. This variety grows only along east central Florida, down to south Florida. It prefers a sandy habitat.

Keywords: about seagrass, marine plants, seagrass varieties

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Lauren Wise has more than eight years' experience as a writer, editor, copywriter and columnist. She specializes in food, wine, music and pop culture. Her writing has appeared in various magazines, including "Runway," "A2Z," "Scottsdale Luxury Living" and "True West." Wise holds a Bachelor of Arts in journalism from Arizona State University.