The Seemingly Harmless Plant was a gift that Timmy Turner got from the Planet of Seemingly Harmless Plants for Trixie Tang. Unfortunately, it was really an alien monster that had a taste for flesh and it could grow at a fast pace.
This innocent looking budding plant looks harmless at first, but when it is taken from its planet to Earth and the clock strikes midnight, it grows into a massive, monstrous, carnivorous plant that will devour any human around it.
At first, the plant resembles a red tulip. However, it starts to grow large vines from its stem and it's flower pedals turn into a mouth with teeth. The plant is able to capture humans with its vines and constrict them, it then knocks them out with a pollen that one of its buds sprays in the victim's face. The plant then presumably eats the victim.
Timmy Turner used his fairies to visit a place called the "Planet of Seemingly Harmless Plants", where he acquired a small flowering plant to give to Trixie. When she took the plant into her mansion home, when the clock struck midnight it began to grow at an alarming rate. It knocked Trixie unconscious with its pollen and tried to eat her heart, then Timmy showed up, battled the plant, and killed it by cutting its stem with a hedge clipper. The Plant first appeared in Class Clown and is likely never to be seen again, as it is currently deceased.
The plant resembles Audrey 2 from The Little Shop of Horrors except it is red and unlike Audrey 2, it has eyes.