Harvest Moon Gameboy Color 2 Power Berry
As with all Harvest Moons there is an ingame item called a Power Berry that boosts your Stamina and lets you do more before becoming exhausted. Most likely you already know about these and that's why you're here. The thing is, this Harvest Moon is different from all the other Harvest Moons in that you find all the Power Berries from tilling your field and not doing misc things in the game.
Good luck and have fun with HM 2 on the Gameboy Color! I recommend checking out Magical Melody for Gamecube!!