This Strategy uses Cob Cannons to kill the Zombies while Garlics divert them away from your Cob Cannons. Dolphin Riders are stopped to buy you more time. This strategy requires a lot of skill, as you need to use the Corn Cobs effectively. This can be used as target practice for Survival: Endless strategies with lots of Cob Cannons.
Instant Kills (optional)
Least Seed Slots: 6.
Start off by planting three Cob Cannons in the top row, and three in the bottom row with to Garlics in front in both rows. Simply add two Tall-nuts in the Pool. You need to aim the Cobs at groups of Zombies, and replace Garlics (or Tall-nuts) when necessary, and you can place Tall-nuts on land if you want. Jack-in-the-box Zombies can pose a threat if they aren't killed quickly, and Dolphin Riders are annoying as well, but this strategy isn't too hard with a bit of practice. Here is a picture of the top (or bottom) row:
C-C C-C C-C G G
C-C=Cob Cannon. G=Garlic.