Potion Brewing is the ability to create potions or concoctions with magical properties and it is believed to be one of the witch basic powers. Since many rituals involve the use of herbs and roots a knowledge of herblore is advisable for a witch. Combined with the use of spells, these poultices are magically charged by witches in order to accomplish their purposes.
Brewed with the necessary herbs or other various ingredients, such as an animal or human body parts, these magical substances can achieve various effects. The effect of a potion depends on the used ingredients or accompanied spell. Potions can be used in various ways. Some potions are meant to be consumed to be effective, while others can be used as creams and lotions on the skin or burned as incense. Due to the nature of these concoctions, which rely more on the knowledge of the medicinal properties of herbs, powders, and poisons rather than on spells and charms, even mere mortals who possess an empirical training, such as physicians, can brew a potion with medicinal or poisonous qualities, but probably less effective and powerful than a potion brewed by a witch. Even Witch Hunters are known to use certain herbs that are toxic to witches in order to weaken them or protect themselves from witchcraft.
The classic iconography of the witch stirring a cauldron has its roots in the ancient pharmacopeia, which widely used medicinal properties of herbs and plants. Witches know also the magical properties of these herbs and their use in spells and rituals. In the sixteenth century, however, it is noted that even doctors and apothecaries resorted mainly to the use of herbs, powders, and bark to cure ailments, taking into account also the legendary and superstitious properties. Hereinafter a list of herbs and plants named in Salem.
- Acacia: an herb mentioned by Anne Hale among the ingredients to steal a baby from its mother's womb through a poisonous potion.
- Agrimony: mentioned by Cotton Mather as an ingredient used in exorcism.
- Cayenne: Mary Sibley mentioned a tonic of Cayenne to sharpen the tongue when she threatened George Sibley to induce him to talk. 
- Bear's Breech: common name of Acanthus mollis, is mentioned by Cotton Mather as one of the ingredients to expel a familiar. 
- Bloodroot: Cotton Mather had used this plant to stun the witch Rose Browning and counteract her witchcraft.
- Cascara Sagrada: mentioned by Tituba. It is a plant with healing properties, perhaps used to relieve Anne's pain caused by the cursed doll. 
- Columbine: common name of Aquilegia, also known as granny's bonnet, is one of the ingredients required in the potion to suppress a familiar mentioned by Cotton.
- Fleabane: one of the herbs employed by Anne Hale to brew a concoction to steal a fetus from its mother's womb. This herb was known to Romans as Inula and was related to Helen of Troy.
- Hellebore: one of the traditional plants associated with witchcraft, this poisonous herb was believed to be used to fly. Cotton Mather has used this plant to create a paralyzing poultice.
- Henbane: a poisonous plant associated with maleficium. Cotton Mather used it to get rid of Brown Jenkins.
- Hyacinth: Another plant employed by Cotton to brew a potion to expel Brown Jenkins. Hyacinths are traditionally associated with spring and rebirth.
- Larkspur: belonging to the deadly Consolida family, this poisonous plant is required in the potion to expel a familiar.
- Mandrake: mentioned by Tituba during the dream walking ritual, mandrake root is a plant belonging to the Solanaceae family with a tap root that resembles a human being. Since ancient times this root was believed a powerful tool employed by witches and sorcerers, with aphrodisiacs and deadly powers, and believed to grow from the semen of the hanged men and to emit a human scream when it is extracted from the soil. Mandrake was also used by Cotton Mather to get rid of Brown Jenkins.
- Mugwort: this plant associated with the nocturnal flight was used by Cotton to create a potion to get rid of Brown Jenkins.
- Nettle: a stinging plant used by Cotton to banish Brown Jenkins from his body. Probably the stinging qualities are the reason why this plant has been used.
- Nightshade: belonging to the infamous Solanaceae family, the deadly nightshade plant has passed into history with the name of 'Belladonna' for its use that the Italian Renaissance women did of it in beauty concoctions. Cotton Mather has used it in a paralyzing concoction to stun Rose Browning. Anne Hale used "black nightshade" to brew a foetus-snitching potion. Given the paralytic qualities of this herbs, it's fair to say that it was required to hold the victim still.
- Orris root: mentioned by Madame Mab as effective against potential infections transmitted by the clients of The Divining Rod when she was interrogated by Increase Mather, while he was inspecting her office. Is a term used for the roots of some Iridaceae, and is used as a potpourri or base for perfume.
- Tannis Root: a mysterious herb used by Anne Hale to steal a fetus from its mother's womb. There's no real-world counterpart of this plant. (See Trivia) 
- Valerian root: referred to as "witch hunter trick" by Mary Sibley, this plant has the power to burn the skin of an attacker, especially a witch. It was donated by John Hale to his daughter set in a pendant to protect her from Sibley's maleficia. In folklore and ancient medicine, it was used as an herbal tea. 
|“||Get with child a Mandrake root...||”|
— Tituba mentioning Mandrake in a spell
Most commonly used in Season One, both Tituba and Mary would use a special potion, applied on the forehead, the bridge of the nose and the lips, or on other parts of the body, in order to ignite their magic. The instances where the potion was used was during the Black Sabbath in the first episode of Season One, when Mary dream-walked into John Alden's mind, when Tituba consecrated Mary for a pact with the Dark Man, when Mary turned Mercy Lewis into a witch and when Mary taught Mercy Lewis to "travel without her body". Thus, this might conclude that the potion gives a witch the abilities of astral projection and telepathy, although the potion itself might explain how a witch develops her own magic as well, acting as a lubricant that helps the fledgling witch to tap into her psychic powers.
Note: Although never mentioned, the potion itself might denote to the infamous Flying Ointment of popular witch lore which was said to have been brewed from the fat of unbaptized infants, bat's blood, wolfsbane, mandrake, belladonna and other psychoactive herbs.
|“||Canis urinam. Dog piss, plus some medicinal plants: Hellebore, Nightshade, Bloodroot in combination. The result is a powerful paralytic.||”|
— Cotton Mather
A powerful concoction composed primarily of poisonous herbs, producing an almost instantaneous paralytic effect on the victim at the moment of its intravenous injection. This potion is so powerful to have an effect even on witches, who are noted for their enhanced physiology. The color of this potion is yellowish, very likely because of dog urine, hellebore and henbane juices. The effect of this serum is variable and when it starts to run out, the victim slowly regains their motor sensitivity.
|“||Take a hair of the witch that bit you. Add bear's breech, Columbine, Henbane, Hyacinth, Larkspur, Mandrake, Mugwort, and Nettle. Suspended in potent spirits. Only one way to destroy a familiar. From within.||”|
— Cotton Mather reads the ingredients
This unusual distillate has the power to expel a familiar from the hapless body that was incubating it. It is obtained from the mixture of certain poisonous herbs in a strong alcoholic drink along with the hair of the witch who implemented the familiar. The effect of this potion has a very rapid effect, pushing the possessed to vomit blood and expel the little demon out of their mouth. Since the familiar will try to cling to the host's throat, the removal may be difficult and requires a certain amount of struggle.
Canker blossom Antidote
A liquid that is able to temporarily alleviate the suffering of those affected by Canker blossom inflicted by a witch with a curse. Once swallowed a few drops of antidote, sores and pustules disappear within a few seconds but the duration of the antidote is temporary and can not cure the disease completely unless properly dosed by the witch who cursed the victim.
Potion to steal an unborn child
|“||Acacia, Black Nightshade, Fleabane, Tannis Root. What do I lack? Ah, yes! Grave Earth.||”|
— Anne listing the ingredients
A singular concoction, turbid and dark as the intentions of the witch resorting to it. This potion requires cooking certain herbs to the point when the liquid becomes dark and dense.
At that point, the potion is filtered into a bottle while it is still steaming. Once cooled, it is used to massage the belly of the woman to whom the witch want to steal the baby. This potion needs to be consecrated with a spell.
- Mary Sibley: in order to again subdue George Sibley's mind to her will, Mary Sibley has prepared an amber color tonic, and following a similar tonic was given to her by Tituba to kill Isaac.
- Tituba utilized different ointments on Mary Sibley, to stimulate the reception of the latter during spells and rituals, for example, the flying ointment used during the ritual to create an astral projection.
- The Essex Hive Elders have been shown many times in the woods around a steaming cauldron, probably intent on stirring a potion.
- Mercy Lewis has used unknown herbs and seeds to prepare Isaac Walton's body in order to sacrifice him and make him her slave after death.
- Dr Wainwright has employed considerable herbs and filters to treat diseases. Some of these medical potions have had strange reactions when placed in contact with the Witch Pox pustules.
- Anne Hale has considerable herbal skills that she used to cure ailments of the refugees, before deciding to use her knowledge for more sinister purposes.
- As shown in Children Be Afraid, some poisonous potions have no effect on witches, probably due of their different enhanced physiology.
- A solution obtained with poisonous plants is, besides a ritual of exorcism, the only known method someone can employ to get rid of the influence of a familiar demon.
- Tannis Root mentioned in Wednesday's Child is a fictitious plant that makes its first appearance in Ira Levin's best-seller novel, Rosemary's Baby, and in the eponymous film by Roman Polanski. Even in Rosemary's Baby, this root was used to facilitate a bewitched pregnancy.