Achievement is generally pretty easy to obtain as long as you pick up rewards from chests/golden rewards from free roam areas.
Any character you select can result in obtaining this achievement. You do not need a specific character for this.
1. Locate chests/golden rewards in free roam areas. For me choosing Duran, I was able to find a seed within the walls of Valsena.
2. Locate an Inn. Within the Inn you should see a magic box (essentially a pot plant box) next to the Inn owner.
3. Place the seed and an achievement should pop when you collect your reward.