Ferroseed @ Eviolite
Trait: Iron Barbs
252 Hp, 252 Def, 4 SpD
Leech Seed is for healing and doing residual damage to your opponent, while Gyro Ball compliments his low speed and is STAB. Stealth Rock is Stealth Rock.
Protect is for stalling and recovery. Toxic can also be used to badly poison grass types.