Board Thread:Plants vs. Zombies 2: It's About Time/@comment-25928375-20150418072324/@comment-24760547-20150425021921

I think the reason this occurs is because the instant use plants might actually have PF abilities, but they can only be activated when they are in their idle or non "exploding" animation. Since these conditions can never be met, (except in Power Lily's case) the PF abilities were never discovered...