A method for improving nutrient density in crops. The crops may be fed to animals to improve health of the animals and/or to improve bioavailability of such nutrients in animals. The method may include providing a humic substance from an organic material, combining the humic substance with at least one nutrient, and growing crops using the combination of humic substance and at least one nutrient. The method may further include feeding the crops to animals. The combination of humic substance and at least one nutrient may be mixed before growing the crops. The at least one nutrient may include copper, magnesium, manganese, cobalt, zinc, and/or phosphate, among others.