Which plant produces the world's largest seed, weighing up to 30 kg?

The plant that produces the world’s largest seed, weighing up to about 30 kilograms, is the coco de mer.

Coco de mer is the common name for Lodoicea maldivica, a palm endemic to the Seychelles islands of Praslin and Curieuse. Its enormous seed is often called a double coconut because of its distinctive two-lobed shape. The mature fruit can weigh substantially more than the seed itself, reaching roughly 25–45 kilograms.

The species became famous because mature coco de mer fruits occasionally washed up on distant shores before the Seychelles were known to Europeans. People once imagined that the nuts grew on underwater trees, inspiring the French name “coco de mer,” or “coconut of the sea.” Their unusual shape also generated legends about the fruit being connected with the Garden of Eden.

Coco de mer palms are dioecious: male and female flowers grow on separate trees. The species is endangered and protected, and its seeds cannot legally be collected or exported freely. The ordinary coconut is larger than many palm seeds, but it does not approach the coco de mer’s record size.