Tutorials/Cactus farming

Cactus farming is the systematic planting and subsequent harvesting of cacti. Cactus farms are useful for acquiring green dye, by smelting the cactus blocks. Interesting, effective and large farming configurations can be achieved by using creative structuring of water source blocks and sand. Cactus growth is achieved on blocks of sand and with an absence of adjacent blocks next to the plants.

Manual designs
Manual cactus farms can be a great start to farming cactus. Manual designs are generally cheaper, easier to build, and more lag efficient than automatic designs. However, manual farms are also less efficient and much slower than automatic designs. If you do not need a large amount of cacti, manual farms should be enough.

Cactus rows
This design is probably the simplest next to looting a desert biome. To build it, simply place cactus in rows 1 space apart from each other. It may be desirable to space rows 2 blocks apart to make harvesting easier without getting pricked. If you are not careful, there may be some loss from the cactus being destroyed.

Diagonal rows
This method of cactus farming allows for the player to harvest cacti without taking damage. It uses a platform and a water canal to collect the cacti. Wait for the cactus to grow and break the upper block while standing on the pedestal. It is not the most efficient nor compact design, but it might do for small farms. It has about a 15% loss rate.

Piston harvester
Generally speaking, the use of pistons in a cactus farm is a very laggy and noncompact way of harvesting. However, in a manual design, the use of pistons can be beneficial as they allow the cactus to be more tightly packed and make it easier to harvest without being damaged. Additionally, since all the cactus are broken at one, there is less for broken cactus to be destroyed.

The schematic shows an efficient way of building a farm like this. The redstone and pistons should be built 1 block beneath the sand. Cacti should be placed on every sand block. A block will need to be placed on the pistons or they will not push up high enough to break the cacti. If you are lacking in slime, gravel or another falling block can be used instead of sticky pistons.

Notice how each cactus is only next to 1 piston and each piston except on the edges is next to 4 cacti. When building, make sure it is same if you want to use the least pistons. The first time you build this, it may be helpful to place the sand and pistons first. You could do this on a level surface, digging an extra block lower for each piston. When you are satisfied that the placement of the pistons is correct, remove the sand and ground where the redstone goes.

Automatic designs
Automatic cactus farms work on the principle that if there is space available above a cactus, but there is a block next to where the new cactus block will be, then the cactus will grow and immediately break off. This principle can be used to create massive yet lag efficient designs.

Tiered cactus rows
If there is space available above a 1 or 2 block high cactus, but there is a block next to where the new cactus block will be, then the cactus will grow and immediately break off, dropping a cactus resource around its base. Water flows can then be used to move the drops from many planted cacti to a single collection point. The trick is to place the breaker block along the same row as the cactus, so that it forces the dropped cactus block into the water. Highly efficient cactus farms can be generated using tiered rows and waterfalls, as seen below.

The player may also put a Torch to prevent freezing in a snowy or freeze-prone biome. Keep in mind that some of the cactus drops can be destroyed by the cactus block.

Automatic harvesting
The concept behind this is done with the setup outlined above, except when constructing your building you need to place blocks two spaces above the sand, adjacent to (but not touching) the sand so that they float in the air. The reason behind this is that when cactus comes in contact with an adjacent block it will auto-shed the segment of cactus touching it. This way, when the cactus grows to its 3rd segment high, your floating block will be adjacent to the cactus, so the top piece will break and fall into the water.

Some notes about this though:
 * When a collectable block touches a cactus it will be destroyed. So sometimes when it auto-sheds itself the collectable cactus block will fall onto living cactus and destroy itself.
 * It may be more beneficial to place the block high enough so that when the 2nd segment attempts to grow it harvests itself. This reduces the waiting period of growth in the initial planting.
 * You want to minimize the number of possible points of contact for a cactus block to make contact and fall back to the living cactus. Using the dense checkerboard pattern, consider using iron bars or glass panes and placing them with the bars/panes separated by 3 spaces on the cardinal direction and 1 space on the ordinal direction. This ceiling pattern ensures that all cactus are only being touched on one side, and minimally so (2 pixels), giving the block plenty of room to escape.
 * It is also possible to make a transport system for the cactus if you place a single water source in the corner of the 'box' you constructed for the farm. When placing the water block, you need to place it on the 2nd block above the ground to create a 'down fall' of water which then produces the required force to allow the water to reach the farthest corner away from the source block. With this setup it is possible to have the newly harvested cactus blocks float to a single collection point.
 * Try to experiment with wooden pressure plates at the collection point. Set up a redstone torch which stops burning when the pressure plate is pressed down by a cactus block.
 * The block adjacent to the top cactus can be a sign rather than a solid block.
 * A minecart with hopper that is in the sand block under the cactus will always be able to grab any item dropped onto the top of a cactus before the cactus can destroy it. (A simple way to get a hopper minecart into sand is to get one into a 1 x 1 hole and drop sand on it). This allows one to create a loss-less cactus farm.

Multilevel Farming
Automatic farms can be stacked on top of each other to increase yield.

Using a design like this, you can create insanely large and space efficient cactus farms. Also, with some water, hoppers, and a chest, you can make it fully autonomous leaving it, and collecting the cactus later.

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de::technik:Kaktusfarm Tutoriels/Cultiver des cactus Кактусовая ферма 教程/仙人掌种植