Tutorials/Bone meal farming

A bone meal farm can be created by connecting a farm of choice to a composter via a hopper or minecart with hopper, to produce bone meal, or using a skeleton farm, since skeletons drop bones, which can be crafted into bone meal.
Most plant farms can be used to generate bone meal. The most efficient farm types to connect the bone meal farm with are melon slice or cactus farms, as either can generate a lot of bone meal per hour if the farm is big enough. Additionally if you have other farms you can make leftovers, such as seeds go into the composter.
== Using a composter ==
Right-clicking a composter is inefficient. Luckily, the game allows us to connect a composter to a hopper: add a hopper on top of the composter to make a queue of items, and add one at the bottom to keep it running after it gets full by collecting the bone meal.
=== Composting spreader ===
This is a design that uses parallel composters. When you have an efficient upstream farm, this is what you need.
Items can be inserted into the composter by placing a hopper on top of a composter. The farm starts by adding unwanted compostable items into the chest on the top left (see picture). The items in the chest occasionally drop into a minecart with a hopper that travels along a track over the hoppers above the composters. The items are taken out of the hopper minecart and into the composter, and composted automatically. When the composter is fully fertilized, the bone meal is taken into the bottom chests.
Alternatively, you can do without a rail by using a large chest with two hoppers below, connected to two different composters. The hoppers divide the input evenly. You can even scale this up to connect to another level of chest-spreader, so you can have 4, 8, 16... composters running in parallel.
=== Villager ===
Make a crop farm and lock farmers in it. Place minecart hoppers under each block of farmland. The hopper minecarts should funnel the crops into hoppers, which point downward to composters. Under the composters should be more hoppers that point to a chest.
This farm requires much iron and wood, so you should make an iron golem farm and have a large supply of wood. See Tutorials/Iron golem farming.
A farm by Chapman
=== Bone meal shearing ===
Bone meal shearing is an unusual way of farming bone meal, and it relies on iron input, as they use up durability on shears.
The process works by composting the flowers which came from placing bone meal on grass.
# Right-click a grass block using bone meal. The more space for grass, the better, as this generates more.
# Shear all the grass and flowers which have just been generated.
# Insert the compostable items into a composter farm of your choice. (See above)
# Collect your bone meal. You regain your original bone meal almost every time (98%), and have a 92% chance of getting some additional layers in your composter. You can probably get extra layers back, which eventually add up to the new bone meal.
# Repeat this process.
Notes:
* If your composter farm has more than 1 composter, you may need to start off with more bone meal. For example, if the farm has 5 composters, you would need to start off with at least 5 bone meal. (You may need a few extra)
* You may also need to get multiple shears in case they break. Putting Unbreaking on shears makes them last longer.
* Using water to automate this does not drop any grass and probably does not give you new bone meal.
== Skeleton farm ==
A skeleton farm can produce bones, which can be crafted into bone meal, as well as other stuff that skeletons drop, such as bows, arrows, and armor.You can also gain XP from them. For more information, read Tutorials/Spawner traps and Tutorials/Mob farm. A spawner trap is the most efficient, because only skeletons spawn:
# Find a dungeon with a mob spawner that spawns skeletons, or build a dark place for the skeletons to spawn. Note that zombies, creepers, and spiders can spawn too in the latter option.
# Make a water stream for the skeletons to fall down to where you want to kill them.
# Kill the mobs yourself, with a mob grinder, etc. to get their drops and XP.
You may put a hopper below the block where the mobs die, so you can collect their drops and put them into a container, or an item sorter.
== Moss-based automatic bone meal farm ==
In both Java and Bedrock Editions it is possible to apply bone meal to a moss block and convert nearby stone into more moss blocks. These can then be composted to make a bone meal profit of between 2.5:1 and 3:1.
The moss can convert stone in a 7x7 area (minus the 4 corners) up to 5 blocks below the source moss block. It can also convert blocks up to 5 blocks above the source, but only where there is a connection of non-air and non-liquid blocks between the moss block and the stone platform above. In any case, only the highest block within the range can be converted. It is also necessary for the source moss block to have air above it for the bone meal to have any effect.
Any moss blocks that are formed, or indeed the source moss block, also have a chance to grow one of the following on top: azalea, flowering azalea or moss carpet. If a plant grows on top of the source moss block it must be cleared before the moss block can be bone mealed again.
To create an automatic farm, stone generators are used to replace the platform that is converted to moss. A mechanism is required to break any moss carpet that grow on top of the moss, usually flowing water or pistons, as this would otherwise prevent any further stone from being converted beneath the carpet. The moss block and other plant items can then be collected and composted. A recycling system is also required to ensure that the farm is self-sustaining in bone meal. 
== Nylium-based automatic bone meal farm ==
In Bedrock Edition it is possible to make a profit from applying bone meal to crimson nylium. The nylium block produces crimson roots and nether fungi in a 7x7 square area around the block that was bone mealed. Collecting these nether plants and placing them in a composter on average yields a bone meal profit. This process can be automated by moving the nylium platform with pistons to break the nether plants. The plant items can then be collected, typically using a water pickup system. from the top of the Nylium platform and fed into a series of hoppers above composters.
== Videos ==
=== Moss-based bone meal farms ===
==== Bedrock Edition ====
==== Java Edition ====
=== Nylium-based bone meal farm ===
==== Bedrock Edition ====
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