Yes, but you need to breed it. By breeding a Pokemon from the Grass egg group who learn Grassy Terrain via level up, with a Pokemon from both the Plant and Dragon/Monster Egg Group and then breed that Pokemon with a Sceptile/Grovyle/Treecko you will end up with a Treecko with Grassy terrain.
Grass Egg Group Pokemon that learn Grassy Terrain:
Level up
Oddish
Gloom
Tangela
Roserade
Tangrowth
Grass and Monster/Dragon Egg Group Pokemon that can breed with the Treecko line:
Bulbasaur
Chikorita
Treecko
Turtwig
Ivysaur
Venusaur
Bayleef
Meganium
Grovyle
Sceptile
Grotle
Torterra