Weed germination is inhibited under dry conditions.
Thus early season drought may actually reduce weed infestations. Drought that occurs after weed emergence toughens or hardens plants. Weed response to severe drought stress includes leaf cuticle thickening, reduced vegetative growth, and rapid flowering. Drought-stressed weeds are more difficult to eliminate with postemergence weed control efforts. Weeds compete with crop plants for moisture, nutrients, and light.