Objectionable odors from agrichemicals can be masked by adding one or more terpene or their oxygenated derivatives to the formulation before, during, or after application. A particularly preferred formulation is a granulated insecticide that includes an insecticidal amount of a phosphoroamido(di)thioate in solid form, a polymeric binder, a small amount of an anticking aid, and a masking agent containing an essential oil that is either mixed throughout the granule or sprayed onto its surface. The essential oil masks objectionable odors from the active ingredient without adversely affecting the storage stability or efficacy of the active ingredient.