Both your flora and fauna will have to be based on some very exotic biology, because it could not contain any water. Basic chemistry of life would have to be very different, so not sure how you can even define plants. Plants (defined as life form using solar energy) are not necessary at your planet, because crystals of unobtainium make the work plants do on Earth (capture sun energy to and provide sustenance to other life forms).
On such planet, with plentiful free energy from oxidization of hydrogen, there would be very little advantage for slow sedentary lifestyle of plants.