Bellossom is a primarily green Pokémon with circular blue eyes and red markings on its cheeks. It has two bright red flowers on its head and green and yellow leaves around its waist that resemble a skirt, all adding to the appearance of a hula dancer. Bellossom's petals are said to be more beautiful the worse the Gloom it evolved from smelled. When it rubs the petals on its head together, it creates a pleasing sound. Bellossom does not possess feet; in the anime, its center-most leaves bent as it was getting ready to spring, suggesting that it uses its leaves as substitutes for feet or legs. However, the Pokédex does classify it as a biped.
Bellossom is often seen dancing and chanting. In particular, Bellossom dances when cloudy weather persists, or when the heavy rainfall season ends and it is drawn out by the warm sunlight. Being the result of an evolution via evolutionary stone, Bellosom is rarely found in the wild, though they can be found in grassy plains.
Two Bellossom appeared in Flower Power in a major role. A girl named Bailey had a pair that she nicknamed Belle and Bella, and she wanted them to be able to do a dance, but one of them was having trouble with the somersault that this dance required.
Bellossom debuted in Murkrow Row when Gold helped Joey get his bag back; it was one of the Pokémon in the bag.
In Bringing up Bellossom, Erika owns a group of Bellossom who presumably help her in flower arrangement. One of them battled Pryce's Swinub during the Gym Leaders' exhibition matches at Indigo Plateau.
When released from a Poké Ball, Bellossom will use its Sweet Scent to put any nearby opponents into a deep sleep. As Bellossom stays on-screen for longer than most Pokémon, this gives the thrower time to power up a smash move. It is also available as a trophy.
"From time to time, these beautiful flower Pokémon will gather in numbers and perform an odd sort of dance to call out the sun. While in the midst of this strange exhibition, their petals brush together to create a peaceful and soothing melody. A Gloom will only evolve into a Bellossom if it's exposed to a Sun Stone."
Bellossom makes a return appearance in Brawl, once again using its Sweet Scent to put opponents to sleep and leave them vulnerable to attacks.
"A Flower Pokémon. After spells of cloudy weather, Bellossom will gather to call out the sun by performing a dance. When exposed long enough to the sun, the leaves on its body will spin around. A Bellossom's Speed is also known to increase with sun exposure. Its main specialty is poison attacks. Also, Bellossom will close its flowers when sleeping."
Bellossom returns as a Poké Ball summon, once again using Sweet Scent to put opponents to sleep.
NA: A Grass-type Pokémon, Bellossom evolves from Gloom, losing its secondary Poison type. It also gets smaller. It's most common to find Bellossom in tropical climates, grouped together and dancing. In Smash Bros., the Sweet Scent from Bellossom can put even the most hardened fighters to sleep.
PAL: Two unusual things happen when Gloom evolves into Bellossom: it gets smaller, and it loses its secondary type, Poison, becoming a purely Grass-type Pokémon. These Pokémon are most commonly found in groups in the tropics. Here, the more damage fighters have taken, the longer Sweet Scent keeps them asleep!
In its Gold and Silver artwork, and artwork made earlier, Bellossom's body is shown with a blue color instead of its usual green. This color is similar to that of its evolutionary relatives and its Shiny color in Generation II.
Bellossom is the only single-type Pokémon that evolves from a dual-type Pokémon while keeping one of its original types.