The Harvest Sprites live on Sprite Island (right), which appears on Spring 8th of your first year. It does not require any Sun Stones to unlock. At the start of the game, you will have one Sprite of each color; Red, Orange, Yellow, Green, Blue, Indigo, and Purple. Each color of Sprite can help you with a different task on your farm. You can unlock more of each "team" of Sprites by befriending them. Every time you reach 10,000 FP with a single member of the team, a "New Friend" event will be triggered and a new Sprite will appear.