A Mandrake is a very rare, passive Mob found in Grasslands and Caves. They are very useful, and on average only 2-5 Mandrakes will spawn per World. They often spawn together in the same area, so finding one will usually result in finding them all. Mandrakes can be used to make the Pan Flute. They can also be used to make Mandrake Soup in a Crock Pot.
When picked at Dusk or Night (or when underground), it will turn into a living Mandrake, following the player around and constantly making noise until morning, after which it will replant itself on the spot. When picked during the Day, it will die instantly and can be obtained as an item. Mandrakes cannot be grown and therefore there is a limited number of them in the world.
With normal damage modifiers, it takes one hit from a Spear to kill a Mandrake (any version of an Axe or Pickaxe will do the same).
Raw or Cooked Mandrakes do not spoil. Raw Mandrake heals 60 Health and 75 Hunger when eaten, and puts all nearby Mobs to sleep (until the next cycle of the day; from dusk until night, from night until daytime, from daytime until dusk).
Cooking a Mandrake will also put the player to sleep (until the next cycle of the day), as well as putting all nearby Mobs to sleep. Eating a Cooked Mandrake restores 100 Health and 150 Hunger, as well as putting the player and all nearby Mobs to sleep (for exactly one day). Eating Mandrake Soup restores 100 Health, 150 Hunger, and 5 Sanity, but does not put the player to sleep.
Pigs, Gobblers, and Pengulls will eat Cooked Mandrakes left on the ground, putting themselves and all nearby Mobs to sleep until the start of the next day (no matter what time it is). Raw Mandrakes will not put the player to sleep. Pigs will also produce Manure (as they would with other Vegetable) if a Mandrake is eaten. Gobblers and Pengulls will eat Mandrakes that are still planted in the ground, putting all nearby Mobs to sleep (except the player).
When picked during dusk or night, rooted Mandrakes will follow the player (through Wormholes as well), hopping around and making a lot of noise. Like most followers, they will back away when the player gets too close. If the Mandrake is attacked, they will run away from the player indefinitely. Once it becomes daytime, the mandrake will root itself back into the ground where the player can then pick the mandrake and add it to their inventory.
If eaten in Don't Starve Together (DST), Mandrakes will put all players in the nearby area to sleep. The Loot Stash has a chance to yield a dead Mandrake, thus making them renewable since the Loot Stash respawns every Winter.
Since Mandrakes are extremely fast creatures and will keep their distance from the player even if they follow them, it is recommended to only pick them during the day if it is the item the player wants. If one is picked at dusk with no weapons, don't be tempted to hit it with your fist, as it will run away and decrease the chances of catching it.
Live Mandrakes can be eaten by Pengulls and Werepigs, which will still trigger the sleep effects.
Changing settings so that mandrakes are set to lots allows the player to obtain many mandrakes. Because cooking and eating them each set the time forward one day, they can be used to unlock all the characters quickly.
There is a page on the Klei website that is nothing more than multiple looping gifs of hopping Mandrakes along with looping audio of the "meep" sound they make.
The Mandrake, Mandragora officinarum as per Wickerbottom's identification, is a real-life plant that has roots in European folklore. Its roots can bear a vaguely human shape and were said to scream when uprooted. The sleep effect caused by cooking and eating Mandrakes is based on the myth that those who hear the scream of a mandrake dies, which itself is based around the fact that the real plant can cause unconsciousness when eaten in sufficient quantities.
Even though Mandrakes are flammable, they will not turn into Ashes when killed with a Fire Dart.
(PC) When the player picks up a Mandrake using the Spacebar, the Mandrake can be planted again, but if the player tries to pick the Mandrake when it has been replanted, the character will start to shake out of control upon attempting and will be unable to interact with the Mandrake again.
(PC) Mandrakes spawned into the player's inventory can be replanted when 'dropped' on the ground. Stacks of Mandrakes will be replanted as if there is only one, and when picked at dusk or night, only one Mandrake will actually follow the player. If killed, a stack of however many Mandrakes was originally spawned will be the number the player receives.
In SW, sometimes a Mandrake can follow the player into the Ocean, essentially walking on water. At daybreak, it will plant itself in the water.
Mandrakes in the player's inventory can sometimes be lost when using the Seaworthy to cross over to SW.