Well it depends on what level the Poke'mon is on, what TM/HM moves you teach it, how powerful the moves you teach it are, what moves it learns on it own, if you take care of it, and if you feed it vitamins (calcium, zinc, protein, etc.). All Poke'mon are equal by greatness. I prefer electric types, but if I had to give you the best grass Poke'mon, that would be either Tropius (found in Marsh game) or Leafeon, get from girl in Haerthome then evolve Leafeon in the eterna forest(by mossy rock)
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Torterra is a Grass and Ground type pokemon.
Torterra is the strongest Grass Pokemon in Diamona and Pearl.
You beat a grass type Pokemon by attacking it with a fire type move/fire type Pokemon. I suggest numel or torkoal since those are the easiest fire type Pokemon to find. You can find them at the Fiery Path at route 112.
Electivire is one of the best electric type Pokemon. You get it by letting evolve Electabuzz by trading when holding a Electirizer.
piplup is the best starter pokermon piplup is the best starter pokermon --------------------------- I chosed Turtwig grass type
You need a grass type, a fire type, a water type, an ice type, your legendary and a ghost or dark pokemon.
Start out with chimchar, shinx, pacharisu, starly, grass type pokemon, and buizel/any other type of water pokemon.
Your best bet is: A Water type An Ice type A Flying or Fire(or Moltres) A Dark or Ghost type(or Spiritomb) A Grass type A Rock type Hope this helped!
A good grass Pokemon in Diamond or Pearl would be Turtwig, his evolutions, Budew, Roselia, and Roserade. Those are the best I can think of. where to find some good grass Pokemon. I'm in the middle of training my Staraptor, and the best place to find some good grass type Pokemon, is the route before Sunyshore City, they are around level 38-43. Good place to train Staraptor, or any ice, fire or flying type Pokemon. x Hope I helped. x
torterra is the best grass type Pokemon Pokemon Pokemon Pokemon Pokemon Pokemon Pokemon Pokemon Pokemon Pokemon VULTRAE:torterra or roserade
The best place to train a lv 30 fire type in Pokemon diamond would be next to snow point city because there are lv 30 Pokemon there that ice and grass but run away from the sneasel.
make your grass type learn other moves
Venasuare
Quagsire is a water and ground type. Since grass is effective on both I'd say that's your best choice.
ice type moves
A female Venusaur and any grass or poison type male.