Ancient Seeds are seeds found in Stardew Valley. They can be received by donating an Ancient Seed artifact to the museum or randomly from a seed maker. Doing so will also reward you with the Ancient Seeds crafting recipe.
Planting Ancient Seeds will cause an Ancient Fruit to eventually sprout. Although it takes a very long time for it's initial harvest, the Ancient Fruit can be harvested multiple times and will last three seasons, Spring-Fall.
To craft Ancient Seeds you need one Ancient Seed artifact.