The leaves of the Venomous Tentacula plant are very valuable. Horace Slughorn was known on at least one occasion to steal them from the Hogwarts greenhouses. Leaves from an unhealthy specimen would not fetch very much money, but an experienced potioneer could brew some dragon dung fertiliser that would make the Tentacula healthy again.
- Harry Potter and the Half-Blood Prince (film) (First appearance)
- Harry Potter and the Half-Blood Prince (video game)
- LEGO Harry Potter: Years 5-7