Unlocking Characters
To unlock the Cliff character, you'll need to fully explore the island's areas. You also need to fully construct the Island Hotel and he will show up between the first and the 25th springs. To unlock Danny, you just need to capture 50 fish, and to get Lanna you need to capture 70.
Harvest Sprites
To get the harvest sprites on the island, just go to certain places. To get Earl, you have to go into the mountains. For Kalen, go to where the meadow is located. In the fores you can get Neil, and Ben is in East Town. Manfred can be gained by going into the jungle, and for Rock, just go to the mountain's summit.
Farmers
To get the different farmers in the game, you'll need to first unlock East Town and the forest area in the game. After unlocking East Town, ship 100 spring crops and you will get Megan. For Sachi, you'll need to ship five summer fruits. These characters don't need the forest area unlocked first. The other characters need the forest area unlocked as well as East Town. After both areas are unlocked, ship 10 summer fruits to get Amy, and for Tina, ship 100 summer crops. For Tess, ship five fall fruits, and for Racquel ship 100 fall crops. To get Rebecca, you'll need to ship 100 rice crops.
Crops
To unlock the different crops in the game, you'll have to do a variety of shipments as well. To get cabbage, do a shipment of 100 wheat crops, and to get cucumber ship 100 spring crops. For onions, you need to ship 100 summer crops, and for wheat you need to ship 100 each of any five crops you choose. Yams will require you to do a shipment of 100 fall crops. For strawberries, pumpkins and spinach you'll need to ship 100 crops from two seasons in the game.