Nether Wart

Nether wart (known as Nether stalk in the coding) is a plant grown in the Nether.

Obtaining
Nether wart can be mined with any tool, or without a tool.

Natural generation
Nether Wart generate naturally in Nether fortresses as a plant, or inside chests there (in stacks of 3 to 7). In Console editions, it is randomly found in Soul Sand patches around the Nether.

Farming
When planted on Soul Sand, Nether Wart will grow through four stages, though the middle two stages have the same appearance. Growth is driven by block ticks. The duration of each stage is random, with no upper or lower limit, but the average duration is about 3 minutes and 30 seconds. The growth rate is not affected by light or any other environmental factors. Bone meal has no effect on the Nether Wart. Nether wart can only be planted on Soul Sand. It will grow in any dimension. Nether warts are ready to harvest when they reach their fourth stage. Breaking a fully grown Nether wart yields 2 to 4 Nether wart seeds, while an immature one yields only a single seed.

Video
Note: The video states that Nether Wart can only be grown in the Nether. This is outdated: since, Nether Wart can be grown in all dimensions as long as it is planted on Soul Sand.

Trivia

 * Nether wart makes "stone" sounds when destroyed.
 * In the code, nether wart is known as "tile.netherStalkSeeds".
 * Nether wart's stage changes cannot be detected by a BUD.