Introduction to coconuts of the sea: When it comes to Seychelles, you have to mention coconuts of the sea. Coconut de mer fruit is the largest and heaviest seed in the plant kingdom, usually around 10 kilograms, and can weigh up to more than 30 kilograms. When it is 7-9 months old, the pulp can be eaten while it is still gelatinous. Once it exceeds 9 months, the pulp will gradually harden.