Minecraft wiki entry for Things_not_to_do, associated text: When they are in its smaller components, they give you more bone meal. Even though the high level of compost is tempting, it doesn't get you anywhere further. For example, using 100 kelp blocks as compost only yields 7.143 bone meal while if crafted into 900 kelp you get 38.571 bone meal, which is more than 5 times as much.