Azos is a naturally occuring bacteria that lives symbiotically with your plant. Applied only once, Azos will live for the life of your plant fixating nitrogen, producing a natural growthhormone IAA (Indole-3-Acetic-Acid) and increasing root structure. Azos works best with Mykos, as both Azos and Mykos work symbiotically with each other as well as with the plant.