Board Thread:Plants vs. Zombies 2: It's About Time/@comment-3560445-20130721102023/@comment-12082018-20130805164706

Also for that matter where is it referred to as napalm? Napalm should look like red and black clouds.

Instead it simply looks like a working flame.

Working flame being generally used in cooking as blue fire on a barbeque or a gas oven or cooktop. They look identical when thought of like that. Plus plant food upgrades plants so it would make sense that the fire is made hotter.