The present invention relates to a composition comprising microcapsules, which comprise a polyurea shell and a core, wherein the core comprises pendimethalin and the shell comprises a polymerization product of a tetramethylxylylene diisocyanate, and a polyamine with at least three amine groups, and where the polymerization product comprises less than 5 wt % of further isocyanate monomers in polymerized form, based on the weight of the tetramethylxylylene diisocyanate; a method for preparing the composition comprising the steps of contacting water, the pendimethalin, the tetramethylxylylene diisocyanate, and the polyamine; and to a method of controlling undesired plant growth, wherein the composition is allowed to act on the soil and/or on undesired plants and/or on the crop plants and/or on their environment.