Berenice was originally found by Edgar and Ellen in the Gadget Graveyard when they were young children. She was just tiny sprout with two little pink "lips". Ellen was extremely excited to see her eat a little fly as it flew by, and since then cared for her by feeding her a variety of insects she and Edgar caught with sticky paper. As she grew, she became entangled in a mattress frame, making her impossible to move.
Though they did their best to stop the removal of their beloved junkyard, the twins failed, and Berenice was injured horribly by a construction worker when they ripped the mattress frame away from her. She was noticed by Stephanie Knightleigh shortly after, who was disgusted at the look of her, and stuck her shovel straight down on her.
Ellen was distraught over Berenice's death, and assumed she was getting sick because of the feelings of loss and the urge to cry that she had never experienced. She insisted that they bury her, and Edgar helped her dig a six foot deep grave. He then offered her a handkerchief as a makeshift burial shroud, and carved her a crude headstone out of a cement block.
- Berenice was large enough to cover and be entwined with an old mattress frame.
- She had a multitude of long vines.
- She grew out of the ground in the Gadget Graveyard.
- Berenice's seeds would fall from her mouth, and her "daughter", Morella, was sprouted from one of them.
Unlike in the books, in the cartoon series Berenice is very small. She has a pointier appearance, and her gullet is noticeably less bulbous, looking more like a chin than a stomach. Her skin is covered larger dots than her book counterpart's, and her mouth looks more like a beak. She still has several tooth-like seeds in her lower jaw, but it's unknown if they fall out nightly like they do in the books. Instead of living in the junkyard, she lives in Ellen's greenhouse in a small red clay pot.
Berenice is mobile in the TV series, instead of being stuck in a mattress frame, and can hop around while still inside of her pot. She even has a set of wheels attached to her pot during "Ellen vs Slug". Her roots are much more versatile, and she can use them to grab objects near her.
Her temperament is no different, and she frequently hisses and snaps her jaws, trying to bite anything that gets close (usually Edgar). Her and Ellen have more personal bond than in the books, and she seems to understand what Ellen tells her, and does not try to snap at her. Ellen often refers to Berenice as "my girl", and talks sweetly to her when she feeds her. During the Halloween special "Trick or Twins", Berenice is turned monstrous by one of Edgar's potions, but recognizes Ellen when she speaks to her, and opts to try and eat Edgar instead.
Her appetite and diet is even more gluttonous than before, and she enjoys eating anything she can get her roots on, including but not limited to; bugs, potions, glass bottles, and Edgar's nose.