It evolves at level 40.
When you say envolve i think you meant evolve so I will tell you the question to on How to evolve ponyta in Pokemon platinum. He just needs to be elevated to level 40.
A fire stone might work, but ponyta's usually evolve at level 40.
ponyta evolves at level 37
Ponyta will evolve into Rapidash at level 40.
ponyta evolves at level 40
Ponyta evolves at level 40.
Level 38.
Level 40.
level 31
Level 34
ponyta evolves at level 40
Ponyta evolves to Rapidash at level 40.