A method for providing nutrients to a plant can include providing a nutrient composition and administering the nutrient composition to the plant or to soil or water having the plant so as to provide the plant nutrient to the plant. The nutrient composition can include: at least one biosurfactant penetrant selected from the group consisting of glycolipids, lipopeptides, flavolipids, lipoproteins, and combinations thereof； and a plant nutrient chelated or complexed with the at least one biosurfactant, the plant nutrient being selected from the group consisting of elicitors, plant-growth regulators, fertilizers, minerals, plant-stress reducing agents, and combinations thereof, wherein the nutrient composition is configured to penetrate into the plant. A method for retaining moisture in a cultivated plant is also disclosed. A method for treating a seed is also disclosed.
