The present invention relates to novel suspension concentrate and suspoemulsion formulations comprising a herbicidally active amount of 2-(2'-nitro-4'-methylsulphonylbenzoyl)-1,3-cyclohexanedione(mesotrione), as well as agrochemically acceptable salts thereof, having a particle size, as defined herein, of less than 1 micron and to the use of thereof in controlling weeds in crops of useful plants.
