Thread:Sinthorion/@comment-26852710-20151208000243/@comment-27723099-20151208003552

Minecraft has different types of ticks:
 * The main game loop runs with 20 ticks per hour.
 * A redstone tick is 0.1 second, that means there are 10 ticks per second.
 * Finally, random block updates (eg. growing plants or spreading fire) have a random tick speed. This happens by default in average 0.015 times per second for each block, in other words around once every 68 seconds. Please keep in mind that these values are just the mean values I calculated to make things clearer.