Blue Lily

Blue Lily is the fifth plant obtained in The Deep Sea in Plants vs. Zombies: The Wacky House. She shoots slowing blue pellets at zombies every three seconds. They bounce off multiple zombies, similarly to, however in the first two bounces the pellets split into two, resulting with one Blue Lily being capable of firing four pellets in one shot. In addition, she is also capable of breathing underwater and being placed on water in Moist Caves. The pellets deal no damage.

Origins
She is based off of the nymphaea violacea (more commonly referred to as the blue lily), a waterlily in the genus nymphaea.

Plant Food effect
When fed Plant Food, Blue Lily will fire a huge pellet that does not multiply, but does ricochet. It slows down zombies it hits for the next 15 seconds by a huge amount, slowing them down 4x instead of the usual 2x.

Winter-mint effect
When boosted by, Blue Lily's projectiles will multiply three times instead of twice, resulting in up to eight pellets to come from a Blue Lily in one shot.

Strategies
Blue Lily is a great stalling plant to use against tougher zombies, especially in hordes. While not exactly as powerful as splash damage, her bouncing pellets can easily slow down huge groups of zombies.

Her Plant Food ability is a unique aspect of Blue Lily not seen in any other plants in the Winter-mint family in the game. The ability to slow down zombies by four times is a huge stalling tactic, however it can be difficult to use in a useful manner due to Blue Lily's rather random attack pattern.

Another great plus of Blue Lily is that she does not require a Helumthus in The Deep Sea or a in Moist Caves, making her an even better auxiliary plant in both those worlds.

She is an optimal choice in Moist Caves once the has been encountered, as not only does she not require Lily Pads, Blue Lily can easily extinguish hordes of Explorer Zombies' torches.

Despite all her strengths, Blue Lily is not recommended to use in Endless Zones because she does not deal any damage. Winter Melon is a better alternative, especially in later levels as he is also a solid crowd controller that actually deals solid amounts of damage and also slows zombies down.