Bulbasaur is a quadruped, reptilian creature that somewhat resembles a toad or a young dinosaur with a spotted blue-green hide. It has three white toes or claws growing out of its four legs, and its eyes are a bright red. The most notable feature of this Pokémon is the onion-like bulb on its back, which grows from a seed planted on its back by its mother at birth. Unlike the parasitic tochukaso mushrooms growing on the back of Paras, which eventually take over its body as it evolves into Parasect, Bulbasaur's bulb shares a symbiotic relationship that is beneficial for both. This allows Bulbasaur to get an enhanced boost of energy from the sun during the day and the bulb to remain growing and strong at night. The bulb also contains many seeds from which it draws nutrients.
Though they usually walk on four legs, a Bulbasaur can rise up on its hind legs. When it evolves into Ivysaur, the bulb becomes a larger flower bud, making it nearly impossible for one to rise on its hind legs.
Most Bulbasaur are domesticated Pokémon, raised by breeders to be distributed as starter Pokémon in the Kanto region. Due to this, they are regarded as mostly well-behaved Pokémon.
Bulbasaur tend to have a strong loyalty to their friends and Trainers. Once annually in Kanto, large groups of Bulbasaur gather in a hidden garden to become Ivysaur. It is unknown whether or not this is the case in other regions.
Bulbasaur can sometimes be found lying in the sun during the day to photosynthesize energy when food is scarce.
When a baby Pokémon, such as Togepi or a newly hatched Bulbasaur, is crying and all other methods of calming down the baby fail, Bulbasaur may use its vines to perform its Bulba-by, where it rocks the baby back and forth in the air and sings to it. This has only been recorded once by humans, making it seem that some people do not even believe that this behavior is real.
Bulbasaur are scarce in the wild. Sometimes they can be found in secret places such as gardens, plains near large sources of fresh water, or hiding in the forest in hollow logs, but overall, they are found far more often in the ownership of Trainers. It is native to Kanto.