Xtreme Gardening Mykos - 100g - 3.5oz Mykos is a fast-growing, beneficial fungus that increases nutrient and water uptake by forming a symbiotic relationship with the roots of a plant. Mykos is needed to break down, cycle, and retain nutrients as well as provide a front line of defense against environmental stresses, pathogens, and diseases. Mykos will continue to grow with your plants becoming an extension of the roots and administering better efficiency and sustainability. With a larger and healthier root system, plants are given the opportunity to increase crop yields and secondary metabolites.