Cactus is a spiky plant block found in deserts and badlands. It grows up to three blocks tall and causes damage upon contact. Cactus is useful for farming, as it can be harvested and smelted into green dye, which provides high XP when smelted in Java Edition.

It is also used to breed camels and can be composted for a 50% chance to raise the compost level. When placed, Cactus destroys items that touch it, making it useful for automated disposal systems. It can only be placed on sand, red sand, or another Cactus block. When placed in a flower pot, it becomes harmless.