Stinksap

• Type: Magical Plant Secretion
• Owners: The plant which produces Stinksap, a Mimbulus mimbletonia, was famously owned by Neville Longbottom.
• Maker: Secreted by the Mimbulus mimbletonia plant.

Stinksap is a thick, non-poisonous liquid that is dark green in color. Its most notable characteristic is its extremely unpleasant smell, which is described as being like “rancid manure.” The substance is housed within the pustule-like boils that cover the surface of a Mimbulus mimbletonia plant. While harmless, its potent and foul odour makes it a highly effective deterrent.

Stinksap's primary function is as a defence mechanism for the Mimbulus mimbletonia. When the plant feels threatened or is prodded, it squirts great jets of the liquid from its boils in all directions.

• Defensive Fluid: Its main purpose is to repel any potential threats to the plant through its startling spray and overwhelming stench.
• Offensive Use: The liquid can be collected and used as a mischievous projectile. The poltergeist Peeves was known to hurl Stinksap at Hogwarts students.
• Commercial Use: Fred Weasley and George Weasley incorporated the substance into their product line at Weasleys' Wizard Wheezes, selling a product known as “Stinksap-Solution.”
• Cleaning: The magical cleaning Charm, `Scourgify`, is effective at removing Stinksap from surfaces and clothing.

Stinksap is first encountered in 1995 aboard the Hogwarts Express. Neville Longbottom proudly showed Harry Potter and Ginny Weasley his new Mimbulus mimbletonia, a birthday gift from his Great-Uncle Algie Longbottom. When Harry suggested prodding it with a wand to see what would happen, the plant sprayed the entire compartment with jets of foul-smelling Stinksap, covering Harry, Neville, Ginny, and a newly-arrived Luna Lovegood. Ginny successfully cleaned the mess with `Scourgify`. In 1997, after the death of Albus Dumbledore, Peeves the poltergeist showed his own form of respect and caused mayhem by “zotting Stinksap at students,” as reported by Professor Minerva McGonagall. During that same school year, Stinksap was also seen as an ingredient in a product for sale at Weasleys' Wizard Wheezes in Diagon Alley.

Stinksap's main narrative function occurs during its first appearance in Harry Potter and the Order of the Phoenix. The incident on the Hogwarts Express serves as the primary introduction for the character of Luna Lovegood. Her calm, curious, and non-judgmental reaction to being covered in the foul liquid immediately sets her apart from other characters and establishes her quirky and unique personality. The event provides a memorable bonding moment for Harry's group and Luna. Later mentions of Stinksap serve to reinforce the characteristics of other figures. Its use by Peeves highlights his anarchic and disruptive nature, while its commercialisation by Fred and George underscores their talent for turning bizarre magical phenomena into popular joke products.

• In the film adaptation of Harry Potter and the Order of the Phoenix, the Mimbulus mimbletonia sprays Neville directly in the face with Stinksap, which appears as a clear, thick goo rather than dark green liquid. (film)
• Stinksap appears as a potion ingredient in several video games, including Harry Potter: Hogwarts Mystery. (video game)