Well... Since these plants were created as a result of Psychic testing, there have been rare chances of a plant gaining a form of sentience, and resistance to attempts to damage it. It tends to be very bewildering when that happens, though none of them have been shown to hold hostile intent.

The Flos Vanus has shown this trait, while the Flos Incubus has yet to have a documented case of it-- mostly since anyone tends to use fire generously upon it, before it could ever reach a stage where it's possible.