Bone Meal

Bone meal is a material that can be used as a fertilizer for most plants, as well as a crafting ingredient for dyes.

Fish
All 4 fish mob variants (cod, salmon, tropical fish, and pufferfish) have a 5% chance to drop 1 bone meal upon death.

Composters
When a composter is completely filled, a single bone meal drops the next time the composter is.

Trading
Wandering traders sell 3 bone meal for an emerald.

Crafting ingredient
$$, bone meal can be also used in banner patterns:

Fertilizer
Bone meal can also be used on the following plants to have a chance to increase their growth stage:

Bone meal does not affect:
 * Cactus
 * Vines
 * Nether wart
 * Chorus plants, or other plants not listed above.

Creating new plants
If bone meal is on a grass block, 0–8 tall grass, 8–24 grass and 0–8 flowers form on the targeted block and on randomly-selected adjacent grass blocks up to 7 blocks away (taxicab distance). The flowers that appear are dependent on the biome, meaning that in order to obtain specific flowers, the player must travel to biomes where the flowers are found naturally. See for more information.

Using bone meal on a non-transparent block that is underwater generates seagrass on that block and its surrounding blocks. Sometimes, coral is generated in its place instead, or if in a warm ocean biome, coral fans may have a chance to generate as well. In order for this to work, there must be 2 water blocks above the block the bone meal is being used on, and the lower one must be non-flowing water.

Using bone meal upon a sea pickle on a coral block creates sea pickles. This generates sea pickles up to 3 blocks (of coral) away, so a 7( + ) X 7( + ) block (49+ blocks) of coral may be necessary, to return the most sea pickles per given bone meal attempt (more attempts grows them more numerously, exactly - including the range of it growing, like grass with heights on grass blocks - as coral and coral fans, though those others being non-solid blocks).

Using bonemeal on netherrack adjacent to nylium will convert the netherrack into nylium of the same type. If both crimson and warped nylium are adjacent to the netherrack that was applied with bonemeal, there is a 50% chance that either type of nylium is created.[upcoming: JE 1.16 & BE 1.16]

Using bone meal on nylium will cause the corresponding roots and and both types of fungi to appear on the nylium block and other nylium nearby, with the type of fungi matching the type of nylium being more common. In addition, using bonemeal on warped nylium will create nether sprouts.‌[upcoming: JE 1.16 & BE 1.16]

ID
Java Edition:

Bedrock Edition: In Bedrock Edition, bone meal has the ID name, with a data value of 15.

Trivia

 * Bone meal can be used on the sides or bottom of a grass block, as well as on a grass block with plants already on top of it.
 * Regardless of if it succeeds in fertilizing, bone meal makes green sparkles. However, like smoke from a torch, the sparkles appear only if the player has particles set All or Decreased.