You need to breed a female Bulbasaur / Ivysaur / Venusaur with a male Tangela, Tangrowth, Sunkern, Sunflora, Roselia, Roserade, Cacnea, Cacturne, Carnivine, Snover, Abomasnow, Maractus, Fonguss, Amoonguss, Ferroseed, or Ferrothorn that know Ingrain.
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