Starfruit

The Starfruit is a plant gained at the end of level 4-6. It attacks with stars going in five different directions: one to the left, one going up, one going down, one going to the upper right (gradient of 1/2), and the last going lower right (gradient of -1/2). Each star does normal damage. It fires these projectiles any time a zombie crosses any of its lanes of fire, so planting multiple Starfruit a bit back from the intended target and overlapping their lanes of fire is a good strategy. If a zombie is exactly In front of the plant and/or eating it, it will be damaged by two of the five sides of the Starfruit.

The actual starfruit is the Carambola, fruit of the Averrhoa carambola, a tree that grows in the Philippines, Indonesia, Sri Lanka and India. The fruit is sweet and extremely juicy, and in cross-section, appears to be a five-pointed star, hence the name.

Suburban Almanac Entry
Starfruit

Starfruits shoot stars in five directions.

Damage: normal

Range: five directions

"Aw, man," says Starfruit. "I went to the dentist the other day and he said that I'm have four cavities. I've got --count it-- ONE tooth! Four cavities in one tooth? How does this happen?"

Cost: 125 (175 in Versus Mode)

Recharge: fast

Standard Levels
Starfruits tend to do their best when zombies are slowed down in other lanes. With their 5-way projectiles, 125 sun cost is very cheap compared to Threepeater (325 sun cost for 3-way projectiles). The real power of Starfuit is when they're arranged vertically (fill a row) or horizontally (fill a lane or two). It's better to use them horizontally while Garlic is planted in front of them, because their straight-up and straight-down projectiles aren't useless. But if there are Gargantuars or Zombonis, you should use the vertical formation, because the Garlic is useless as they will smash or crush them. The Starfruit can also be an alternative plant for Digger Zombies, but you are probably better off using Split Peas or Magnet-shrooms if you are only dealing with them. If you don't need range, two or three Gloom-shrooms combined with Garlic should do instead. It is also worth noting that when there is a zombie next to a Starfruit, its damage output doubles.

Seeing Stars Mini-game
You don't have any choice here, you have to plant Starfruit wherever there is a Starfruit outline - no other plants can be planted there (except the Pumpkin). In order to win the game, you have to plant one Starfruit in each outline. Just build up a regular defense with a row of Sunflowers in back, with a row or two of Peashooters and Snow Peas, to protect the house as you set up the Starfruit. For the third lane, plant a Garlic on the right-most row.

You don't have to choose Starfruit in that level but it is required to win the game.

Trivia

 * Unlike other offensive plants, the Starfruit does not try to harm a Bungee Zombie that is stealing it. But if a zombie is in the Starfruit's range and a Bungee Zombie is trying to steal another plant, all five stars will shoot at the Bungee Zombie until the zombie is out of the Starfruit's range.
 * The Starfruit is the only plant that can shoot 5 projectiles at a second. This means that the plant can shoot the the second most projectiles at the same time (five), with the Gloom-shroom coming first (eight).
 * The Starfruit, the Gloom-shroom, the Cattail, the Cob Cannon and the Threepeater are the only plants that can fire outside the lane they're planted in.
 * The Starfruit, Marigold, and Cattail are the only plants with one tooth.
 * In some instances, a zombie which is not on the Starfruit's range will still be hit by the plant if another zombie on another lane is on its range.
 * The Starfruit, the Wall-nut and the Cob Cannon are the only plants with Mini-games featuring themselves.
 * It is the only projectile-shooting plant that cannot shoot in its own lane by itself.
 * When it shoots it should go in the shape of a star but it is misaligned at the top so it would shoot directly above it.
 * The stars the Starfruit shoot actually come from the middle of the Starfruit.
 * The Starfruit opens it's mouth when it attacks.
 * Starfruit is the only plant that lies down.
 * The Starfruit and the Threepeater are the only plants that has different cost and, at the same time slower recharge time in Versus Mode.
 * In the DS/DSi versions, the Starfruit is not as effective. Sometimes, a zombie may be within its range, but the star projectile will just bypass the zombie instead of hitting. This most likely occurs if the zombie is in a lane above the Starfruit, regardless of position.
 * The Starfruit and the Gloom-shroom are the only plants that face directly upwards.
 * The Starfruit, the Winter Melon, the Melon-pult, and the Cherry Bomb are the only plants that are fruits.