Money can be earned in several ways:
- Killing Zombies (sometimes coins, diamonds, chocolate, or Zen Garden plants may drop), and killing a Zombie Yeti will drop five diamonds (four on later encounters).
- Leftover Lawn Mowers, Roof Cleaners, and Pool Cleaners (they turn into gold coins after each level and are automatically collected)
- Marigolds (they drop coins and occasionally diamonds at intervals)
- Completing Levels (when Mini-games, Puzzle Mode levels, and Survival Mode levels are completed, a money bag or trophy is dropped; clicking on it will cause gold coins or diamonds to be automatically collected)
- Eating Brains in I, Zombie (coins, diamonds, presents, or chocolate may drop)
- Every few levels in Vasebreaker Endless (the last vase will drop a money bag)
- Completing Adventure Mode levels after beating them for the first time (the last zombie will drop a money bag with 5 gold coins in it)
- From Zen Garden plants (Zen Garden plants drop money after being watered or fertilized, as well as after the Phonograph or Bug Spray is used on them. After the Phonograph or Bug Spray has been used, they also drop occasional coins in a manner similar to Marigolds.)
- Destroying a Grave with a Grave Buster (coins, diamonds, presents, or chocolate may drop)
- Selling Zen Garden plants (directly adds a certain amount of money to the bank balance; this amount depends on the type of plant and its maturity)
Note: Gold Magnets do not drop money, but only collect it.

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