Giant pumpkin

In one of Locke's quests, he gives Arco a pumpkin and asks him to grow a giant pumpkin. He says: Sow pumpkins seeds at night and make the moon shine on them.

To turn grow a giant pumpkin:

Giant Pumpkin is the only crop that does not have its own unique seed; rather, it is grown from a generic pumpkin. Plant the pumpkin at night, when the moon is visible in the sky. Move Arco and/or rotate the view until the pumpkin icon above the field is positioned in front of the moon. If successful, the icon will immediately change to reflect a giant pumpkin (there is no guessing aspect!). Note that this will not work for pumpkins that were planted during the daytime.

Note that the field will always produce exactly 1 Giant Pumpkin, regardless of level