An aqueous composition suitable for applying insecticides or acaricides to plant propagation materials comprising water, an insecticidally or acaricidally effective amount of at least one nitroimino- or nitroguanidino-compound in free form or in agrochemically useful salt form and a blend of the following components, by weight:a) 2-10% of a surface-active agent comprising a1) at least one anionic surfactant;b) 4-20% of at least one inorganic solid carrier; andc) 3-25% of at least one antifreeze agent.