Minecraft wiki entry for Crop_farming, associated text: Crops can be harvested at any time by left-clicking on them with or without a tool, but when immature, they yield only one of the corresponding seed item. When mature, wheat yields 0-3 seeds and one item of wheat. Carrots and potatoes yield 1-4 of the crop when mature. Mature potato plants have a 2% chance of dropping a poisonous potato in addition to the normal potatoes. Beetroots drop 0-3 seeds and 1 beetroot.