Zombucks

Zombucks are a currency item dropped by zombies, and are given to the player as rewards for completing quests and beating stages in road-trip mode in Plants vs. Zombies Adventures. They are used in town mode to buy and upgrade buildings and place decorations. Once the player finishes Cadaver Cavern, they can also use 3,000 ZomBucks to buy a fifth plant spot for use in battles (normally, a maximum of four plant types can be chosen). A sixth slot can be bought once the player reaches U of Z.

Ways to earn them

 * Killing zombies (not very common)
 * Invading other people's towns with zombies
 * Surviving a zombie sneak attack in the player's town
 * Completing a Road Trip level
 * Leveling up
 * From Treasure Chests

Ways to spend them

 * Buying and upgrading buildings
 * Buying decorations
 * Adding seed slots

Purchasing with Gems
Zombucks can be purchased with gems at the following exchange rates: