Sprout is wild and tends to be aggressive, often trying to bite people when he was still confined in a flower pot. After he rooted into the ground and grew to enormous proportions, he became very dangerous, spreading his vines like weeds to attack victims. However, he apparently calmed down after being uprooted and contained. He also seems to like Lilo.
Sprout is a plant-like experiment with a purple head shaped like a Venus flytrap, giving him a lizard-like face and sharp teeth. He has dark blue pupil-less eyes, three leaves surrounding his head like a frill, and a single antenna on his head. His body is leaf-like, with a thick green stem extending to his head and containing eight tentacle-like vines.
Powers and abilities
Sprout can grow from a small experiment to an immense monstrosity at a rapid rate. Using his burrowing capabilities, Sprout can initiate his growth once he roots into the ground, allowing him to sprout a destructive forest of vicious duplicates, and sends out tendrils that can grow new heads and act like weeds, all with replicas of Sprout's head.
Experiment 509 was the 509th genetic experiment created by Jumba with Hämsterviel's funding. He was designed to spawn into an uncontrollable killer forest. 509 and the other first 624 experiments were deactivated and smuggled to Earth by Jumba during his mission to capture Experiment 626.
509's pod eventually made its way into a post office, where Lilo found it on the floor while she was mailing a letter to her pen pal Henry. She then took the pod home to Jumba who described 509's powers, but Jumba, unwilling to risk activating 509 due to the destruction the latter would cause, locked the pod away.
However, the following night, Lilo and Stitch stealthily stole 509's pod from Jumba's desk drawer. Lilo then activated the experiment, named him Sprout, transplanted him, and fed him super-fertilizer.
The next day, Lilo took a rapidly-growing Sprout to an outdoor orchid competition. When Mertle approached Sprout and noticed he was not an orchid, Sprout lashed out at her, causing Mertle to accidentally break his pot open.
Sprout then rooted into the ground and grew into a massive forest of killer plants, which took over the Kokaua Town fair, causing widespread panic and Stitch to lose the rodeo to a five-time champion cowboy.
Eventually, Stitch managed to lasso the original Sprout, uproot him, and drag him into a pineapple-shaped water tower slated for demolition, trapping the latter and causing the forest to die off without the original Sprout. Lilo was unsure if this was truly Sprout's one true place, but it was the best she and Stitch could do on such short notice.
The first 624 experiments, including Sprout, were rounded up by Leroy and taken to a stadium to be destroyed. However, Lilo, Stitch, Jumba, Pleakley, Reuben, and Gantu arrived before the experiments could be destroyed.
Sprout participated in the following battle between the experiments and the Leroy clones.
The Leroys soon gained the upper hand in the battle, but were defeated when Lilo, Stitch, Reuben and several other experiments performed the song "Aloha ʻOe", which caused the Leroy army to shut down due to the original Leroy's fail-safe. Sprout joins them for the song by playing the drums.
Sprout was mentioned twice in the Stitch! anime. In "Shogun", it is shown that Sprout was dehydrated back into an experiment pod and locked in Jumba's vault.
Though Sprout did not officially appear in the exclusive episode's English dub, his son did. It is revealed that Sprout can produce seed pods and launch them into space, where they cling to asteroids. One of these pods landed on the island and grew into a "Sproutling" (509-A) that carried out Sprout's original programming before being neutralized.
In "Sprout 2.0", Hämsterviel reveals that he has enhanced another one of Sprout's seedlings with the DNA of Experiment 627, disguised it as a plant, and hid it on a deserted island in an attempt to capture Stitch. Gantu and Reuben disguise themselves and convince Stitch and the gang to go find a flower that grants wishes, but is truly the seedling. Shortly after arriving on the island, the gang finds and almost instantly captures the seedling. However, when the seedling escapes, 627's DNA causes him to become unstoppable. Luckily, this also gave the seedling 627's only weakness: laughter.
- Sprout was first revealed in a DVD bonus feature of Stitch! The Movie in the experiment gallery.
- Sprout is an obvious parody of Audrey II from Little Shop of Horrors.
- Sprout bears a great resemblance to most real-life Venus flytraps.
- Sprout's pod color is blue.
- Sprout's holographic silhouette appeared in both "Amnesio" and "Fibber".
- Sprout is shown to have two different graphic designs on Jumba's computer.
- In the battle between the Leroy army and the experiments at the end of Leroy & Stitch, Sprout did not grow into an uncontrollable forest of destruction like he did in his debut.
- In the English dub of Stitch!, Sprout is said to produce seeds called Sproutlings (a.k.a. Experiment 509-A) that carry out the same primary function as their father.
- According to Jess Winfield, Sprout was originally going to be named "Weedy" at one point.