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|First Appearance||Alpha 1.0.6|
|Type of Block||Solid Block|
|Data Values||Hex: 51 Dec: 81|
Here are two good options for farming: automatic farms, and manual farms. Automatic farms can involve pistons and redstone to push the blocks, forcing their gravity-affected nature to come into play. The other option for cactus farming is to simply place a block above and beside the single block of cactus, whenever the cactus attempts to grow, the block will be destroyed because of the cactus's inability to be adjacent to other blocks. One good way to make a farm is putting water around a cactus and a room under the cactus to catch items. You will be damaged if you go near a cactus. You can only place them on sand.
Cacti will destroy any item that come into contact with them, including harvested cacti blocks. If a player dies by cacti, it is likely that many of their dropped items will be destroyed. Therefore, making traps with cacti in order to farm resources can be less efficient. Cactus can be cooked in a furnace to make cactus green dye. Cacti can be used to protect your house from monsters by using two to three-block-high cactus, and then putting a netherrack block in the ground next to the cactus, then lighting it on fire. This is a common and simple wall which is good against all mobs. Another form of cactus defense is to surround your home with cacti in a wall, with each cactus diagonal from the next one. This is also very efficient, and is easier to make since it does not require traveling to The Nether or anything that might be difficult to obtain. You can also place cacti in flower pots; this way they will not hurt you and you do not need to worry about them being next to a wall.