Abstract: A method for improving the health of a plant, comprising treating a plant growing on soil or soil substituents and/or treating the locus where the plant is growing or is intended to grow with at least one (thio)phosphoric acid triamide according to the general formula (I) wherein X is oxygen or sulfur, R1 and R2 are—independent from each other—H, substituted or unsubstituted 2-nitrophenyl, C1 to C20 alkyl, C3 to C20 cycloalkyl, C6 to C20 heterocycloaryl, C6 to C20 aryl, or dialkylaminocarbonyl group wherein R1 and R2 together with the nitrogen atom linking them define a 5- or 6-membered saturated or unsaturated heterocyclic radical, which optionally comprises 1 or 2 further heteroatoms selected from the group consisting of nitrogen, oxygen, and sulfur, wherein improved plant health is determined by —increased crop biomass or crop yield, —improved plant vigor, —improved plant quality, and/or —improved tolerance or resistance of the plant to abiotic stress factors.