The present invention is directed to methods for enhancing root growth comprising applying a S-Benzylthiouracil compound, or a salt thereof, to a plant, plant propagation material, root zone, or root of a plant. The invention also relates to methods for reducing the harmful effects of environmentally stressful conditions on plants, such as drought, or intense temperatures, by application of a S-Benzylthiouracil compound, or a salt thereof, to a plant, plant propagation material, root zone, or root of a plant. The invention further relates to new S-Benzylthiouracil derivatives, and salts thereof.
