Complex sentence: Bushroot has the ability to control any and all forms of plant, though some seem to obey better than others, and he sometimes has to use chemicals or fertilizers to make a plant of any actual use in a fight.
Split into simpler sentences: Bushroot has the ability to control any and all forms of plant, though some seem to obey better than others. He sometimes has to use chemicals or fertilizers to make a plant useful in a fight.