On the main menu select play garden, then choose to create a new garden, when asked to name your garden, name it Piata People. You'll start the garden you named, but you will unlock ability to view the credits on the main menu (the sign farthest to the left). When you view the credits you have to break open the Piatas (one hit breaks them) to see them, before you break them open, you might want to destroy the debris to unlock the hidden accessories. This mode is completed after you break all the Piatas. You will also unlock The Wishing Well when you complete this mode.

Unlocks Credits Mode - Piata People