The present invention relates to a 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.