This level is not very hard. Celery Stalker, although it does a huge amount of damage, but it can easily be overwhelmed by hordes of zombies or zombies with special ability such as the MC Zom-B, so it should be treated as the early offensive plant. Cactus however can attack at better distance, so it should be the main offensive plant. The player also may think about feeding the Cacti Plant Food to make the level easier.
Due to Thyme Warp's very slow recharge, the player should only use it when things get too tough.