Once players in a pack find out this exploit exists, almost every generating flower can be cheesed. This was fixed in the botania 1.14: VazkiiMods/Botania@bda4cc7

A different approach might be needed because I don't think this functionality in json files exists in 1.12.

Thanks for your concern but this is not a problem in 1.12; the Botania-side bug linked was a regression from 1.12.

Even if you make a flower decayable with btweaks it saves its current decay state to the item.