The Zen Garden is an additional mode in Plants vs. Zombies and is unlocked after completing level 5-4 in Adventure Mode. The Zen Garden lets you grow and raise plants and in turn, the plants give you money. All plants besides the Flower Pot, Imitater, and the Upgrade Plants (such as the Gold Magnet and Gattling Pea) can be obtained and grown in the Zen Garden. The Zen Garden is useful in which you can lots of money that are dropped by the plants you are raising. Once the plants have been fully grown and watered and sprayed with bug spray or listened to the phonograph, they will drop money endlessly untill the computer/DS/iPod/iPad/PS3 or XBOX's clock hits midnight and they will need water again. If you have a full Zen Garden, getting money should be no problem however, you will need lots of patience. Marigolds can be bought by Crazy Dave 3 times a day and they will give out more money than other plants.