Appearing in The Green Menace
Leonardo waters his prized "sewer weed" and his brothers make fun of him for it for some reason. They watch April report on the "Annual Flower Show" on TV, when suddenly she is snatched up by a giant vine. Naturally, the Turtles head out to save her.
The Turtles free April, but then she gets a report that a giant tree has suddenly sprouted up downtown. While they investigate this, a vine delivers a VHS tape to the police, who play it on TV. A weird plant guy calling himself Father Nature demands $10 million be paid to him by midnight at the Botanical Gardens, or he will sic his plants on the city.
The Turtles go to stop him, making their way through venus fly-traps, only to find that "Father Nature" is just some bloke in a suit. Called Michael Meebly, he was a botanist who went deep into the heart of the Congo to steal a rare fruit that would allow the consumer to commune with plants. He ate too much of it, though, and now can psychically control plants.
The Turtles attack him, and as April tries to get some footage, she gets captured by a venus fly-trap. Donatello brains Meebly so hard he gets amnesia, forgetting not only who he is but how to control plants. He's then taken away by the cops.
Back in the sewer, Leonardo finds that his sewer weed has died of thirst, despite him watering it just the day before. Leo says that it's okay, because he's had his fill of plants for a while.