Mandrake

Mandrake is a poisonous plant whose humanoid-shaped roots have many magical properties. The necropolis of Fen Carn is said to have an unusually large "population" of female mandrake plants.

A fresh mandrake is considered so toxic that the earth surrounding one is poisoned by the plant and that even breathing in the fumes or sprinkling the fresh juice onto a cut hand can have fatal consequences. At the very least, even if one doesn't die from it, the toxin secreted by the root causes powerful hallucinogenic effects. As such, care is taken to use a mask and gloves to pick them.^[1]

Notable among mandrake's many alchemical uses is its use in the potion that maintains the longevity of sorcerers, preventing further ageing (but not restoring lost youth).^[2]

Folklore

Despite all the rumors regarding mandrake, many of them aren't true. Some common myths include them being powerful aphrodisiacs, screaming when plucked, and being able to curse the one who pulls them out of the ground. The latter two in particular is believed to be a side effect from breathing in the hallucinogenic toxins as, like any other plant, the mandrake lacks vocal cords.^[1]

Encyclopaedia Maxima Mundi entry

Mandrake, or Love Apple, is a class of plant from the Mandragora or nightshade family, a group including herbaceous, stemless plants with parsnip-like roots, in which a similarity to the human form may be observed; the leaves are arranged in a rosette. M.autumnalis or officinalis, is cultivated on a small scale in Vicovaro, Rowan and Ymlac, rarely found in the wild. Its berries, which are green and later turn yellow, are eaten with vinegar and pepper, while its leaves are consumed raw. The root of the m., which is a valued ingredient in medicine and herb lore, long ago had great import in superstitions, particularly among the Nordlings; human effigies (called alruniks or alrunes) were carved from it and kept in homes as revered talismans. They were believed to offer protection from illnesses, to bring good fortune during trials, and to ensure fertility and uncomplicated births. The effigies were clad in dresses which were changed at each new moon. M. roots were bought and sold, with prices reaching as much as sixty florins. Bryony roots (q.v.) were used as substitutes. According to superstition, m. was used for making spells, magical philtres and poisons. This belief returned during the period of the witch hunts. The charge of the criminal use of m. was made, for example, during the trial of Lucretia Vigo (q.v). The legendary Philippa Eilhart (q.v.) was also said to have used m. as a poison.

Effenberg and Talbot, Encyclopaedia Maxima Mundi,
Volume IX

pg. 103, Baptism of Fire (UK edition)

The Witcher

Mandrake is an alchemy ingredient and can be found in the kurgans outside the hermit's hut.

Source

After completing the Daily Bread quest, Geralt can give any meat food to the elves in and around the cave. Any elf inside the cave at night will unlock han and mandrake root in return.
Ritual Plants

Notes

Abigail gives Geralt two of these with the cash reward upon completion of The Barghest Contract in Chapter I, but it does not unlock the ingredient entry.
Several are required for Hunting the Wild Hunt in Chapter IV. They can be found in the kurgans outside the hermit's hut.

The Witcher: Versus

Players can now pay "real world" money to buy mandrake (), which can be used within the game to buy alchemical items like potions, etc. Players who participate in special Versus events can also win mandrake.