Scurvy-grass

• Type: Potion Ingredient, Magical Plant
• Primary Use: Ingredient in the Wit-Sharpening Potion
• Suppliers: Student store cupboard at Hogwarts School of Witchcraft and Wizardry; likely available at apothecaries such as the Apothecary in Diagon Alley.

The specific appearance of magical Scurvy-grass is not described in the novels. Its name is derived from a real-world Muggle plant, Cochlearia officinalis, also known as Scurvygrass. This plant typically has fleshy, dark green, heart- or kidney-shaped leaves and produces small white flowers. It is unknown if the magical variety shares these physical characteristics. As a prepared Potion Ingredient, it is kept in jars in the student store cupboard in the Potions classroom dungeon at Hogwarts.

Scurvy-grass is a key ingredient used in the brewing of the Wit-Sharpening Potion. This potion allows the drinker to think more clearly and is considered an important enough brew to be included in the Ordinary Wizarding Level (O.W.L.) examinations. The inclusion of Scurvy-grass is essential for achieving the potion's desired effect.

Scurvy-grass is mentioned during Harry Potter's fourth year in a Potions lesson with Professor Snape. The fourth-year students are tasked with brewing the Wit-Sharpening Potion, and Scurvy-grass is listed on the blackboard as one of the required ingredients, alongside ginger roots and armadillo bile. During this lesson, Hermione Granger successfully brews a perfect potion, earning praise even from Professor Snape. The lesson takes a dark turn when Snape, suspecting Harry Potter of theft, accuses him of stealing ingredients from his private stores. While Scurvy-grass was an ingredient for the day's lesson, Snape specifically cites boomslang skin and lacewing flies—ingredients for Polyjuice Potion—as the items he believes Harry stole, creating a tense confrontation in which Scurvy-grass was merely part of the classroom setting.

• The name of this plant is a direct reference to the real-world Scurvy-grass. In Muggle history, this plant was highly valued by sailors for its high Vitamin C content, which effectively prevented the disease scurvy on long sea voyages.
• There is a thematic link between the plant's real-world use and its magical one. Just as the Muggle plant “sharpens” a person's physical health by staving off disease, its magical counterpart is used in a potion to “sharpen” the mind and wit.