Kelp is a plantable underwater plant block added to Minecraft in Java Edition 1.13 and Bedrock Edition 1.4.0.
Smelting it in a furnace, smoker, or campfire yields dried kelp. Players can eat dried kelp very fast, faster than other foods. 9 dried kelp can be crafted into a dried kelp block which can be used as a source of fuel.
Wandering traders will sell kelp in exchange for emeralds.
Coral and kelp in the depths of an ocean biome.
Tall kelp, which can stretch several blocks above the ocean floor.