The present invention relates to a composition comprising a first salt, which contains a first anionic pesticide (A1) and a cationic polyamine (B), and a second salt, which contains a second anionic pesticide (A2) and a cationic polyamine (B), wherein both salts contain the same cationic polyamine (B), and wherein the cationic polyamine comprises at least two amino groups. It further relates to a method for preparing said comprising the step of contacting the first salt and the second salt. In addition, the invention relates to a method of combating harmful insects and/or phytopathogenic fungi, which comprises contacting plants, seed, soil or habitat of plants in or on which the harmful insects and/or phytopathogenic fungi are growing or may grow, plants, seed or soil to be protected from attack or infestation by said harmful insects and/or phytopathogenic fungi with an effective amount of said composition. It also relates to a method of controlling undesired vegetation, which comprises allowing a herbicidal effective amount of said composition to act on plants, their habitat or on seed of said plants. Finally, the invention relates to seed comprising said composition.