Harvest Miracle Liquid Plant Nutrient is a yield enhancer that is scientifically proven to deliver up to a 25% increase in yield of dried flower. Yield enhancement comes with no impact to other aspects of the plant. In fact tests have proven an increase in expression of terpenoids and cannabinoids. The copper in Harvest Miracle stimulates an existing enzyme in plants that enhances the availability of iron—a crucial ingredient in the production of chlorophyll, the pigment that makes plants green.