The Venomous Tentacula was a sentient magical plant that had multiple ways to catch prey and terrorise spellcasters alike. It had mobile vines which grab their target, as well as venom from its spikes and shoots. It could also deliver a deadly, venomous bite, and Venomous Tentacula juice was also poisonous, and would turn the drinker's skin purple.

If needed, the best defence against a Venomous Tentacula was the Severing Charm. Along with a penchant for biting humans, they commonly ate Chizpurfles and Doxies. Despite the seeds being a Class C non-tradeable substance, Venomous Tentacula were often kept as pets by wizarding households. The leaves were also a valuable potion ingredient, and used in Potion № 07.

During the Battle of Hogwarts, Professor Sprout and Neville Longbottom used Venomous Tentacula in the offence against the Death Eaters, to great success.