Minecraft wiki entry for Sea_Pickle, associated text: Using bone meal on an underwater sea pickle placed on top of a living coral block creates more sea pickles. Specifically, the colony to which bone meal is applied increases in size, and any coral block within a radius of 2 blocks (rectilinear distance, horizontally from either the coral block or the sea pickle itself) can generate 1-3 sea pickles. They do not grow or spread naturally, and do not require light.