The Botanical Booster is an unstable growth hormone potion distilled from a mentally tormented mackerel's bones and created by Dexter. It appeared in the episode "You Vegetabelieve It!". The potion can accelerate the growth of plant life in mere seconds or revive dying plants. Just two drops is enough to give a plant enough nutrients to fully grow and more than 2 drops causes it to grow into a larger and more beautiful variety of plant. However, using the entire potion will mutate plants into giant and monstrous carnivorous plants, as shown when Dee Dee used it on her plant and Mom's Garden.
- "I'm a mackerel! Now get me out of this mayonnaise jar!"
The mackerel this potion was made from has sentience and is capable of speech (likely due to being experimented on by Dexter) and constantly screams for others to take him out of his mayonnaise jar.