yes you can.
Shroomish is a Grass type pokemon.
you can't
Shroomish is a rare Pokemon in Ruby and Saphire but you can find it in the Petalburg woods.
Shroomish > lvl 23 > Breloom
Shroomish is not available to be caught in the wild in Pokemon FireRed, it must be traded from Ruby or Sapphire.
mostly under ground
Shroomish > lvl 23 > Breloom
It would be in a swarm. It would be on random days though. Shroomish is in Route 11 during a swarm, but unfortunately, Shroomish is only in Pokemon Black.
To encounter Rotom in Pokemon Platinum, check the TV in the Old Chateau at night.
Shroomish evolves into Breloom, starting at level 23.
Breloom!
Shroomish