Marigold

A Marigold is the only money producing plant. It is also the first plant the player gets in the Zen Garden.

Suburban Almanac Entry
Marigold

Marigolds give you silver and gold coins.

Special: gives coins.

Marigold spends a lot of time deciding whether to spit out a silver coin or a gold one. She thinks about it, weighs the angles. She does solid research and keeps up with current publications. That's how winners stay ahead.

Cost: 50

Recharge: slow

Usage
Planting the Marigold costs 50 Sun. Every 24 seconds or so it produces either a silver ($10) or a gold ($50) coin. Gold coins are rarer than silver coins.
 * Note: These are best used in conjunction with Gold Magnets, as you'll probably be too busy tending your other plants to collect the money yourself.

Strategy
Marigolds are great space fillers in early levels due to the lack of higher level zombies and potential for hoarding excess Sun. In later levels Marigolds take up too many valuable slots to be worthwhile (especially on the Roof).

Another strategy is to plant an entire row of Marigolds with a Gold Magnet at the end and two Garlic or Imitater Garlic plants in the front to divert the zombies away. But Catapult zombies can get annoying sometimes.

Marigolds are commonly used in the Mini-game Last Stand for Gold Farming.

Trivia

 * Marigolds is the only plant that can be bought for the Zen Garden.
 * Though Marigolds planted in the game modes all have white petals, Zen Garden Marigolds come with many different petal colors such as red, blue, green etc.
 * During a level's final wave, both Marigolds and killed zombies stop producing coins. Even newly-planted Marigolds will only produce three coins or so before stopping.
 * Marigold sprouts can be seen growing in the loading bar on the title page before a Zombie head shoots out on the lawn.
 * The fact that it produces coins is a pun on its name which has the word gold in it (Marigold).
 * The Marigold actually resembles a Common Daisy more than a Marigold.MArigold_lawn.jpg
 * This is one of the rare plants that don't have any offensive or defensive abilities.
 * The Marigold is one of the plants that glow. The others are Sun-shroom, the Magnet-shroom, the Gold Magnet, the Sunflower, and the Twin Sunflower
 * If you look closely, you will see a single tooth on the Marigold's mouth. She shares this trait with the Starfruit.
 * Following to Marigold's Suburban Almanac entry, she's a female. This makes her the only female besides the Cactus.
 * The Marigold is one of the only flowers in the game (the others being Sunflower and Twin Sunflower).