Method for producing metabolites from plants cultivated in soil-less medium

Method of producing molecules from plants, characterized in that the said plants are grown in conditions above ground and are fed by a nutrient and / or are sprayed with a washing liquid solution, being said solution and / or said liquid then recovered (a) (s) and treated (a) (s) to remove certain specific molecules thereof containing (n) and have been released by the roots and / or aerial parts of said plants.