The present invention relates to a liquid pesticidal composition comprising: (i) a pesticidal mixture comprising, at least one polyalkyleneoxide modified heptamethyltrisiloxane and a matrix-forming agent selected from the group consisting of tetraethyl orthosilicate, tetramethyl orthosilicate, and combinations thereof; (ii) one or more alcohols selected from the group consisting of primary, secondary and tertiary alcohols having between 2 and 10 carbon atoms; and (iii) water. The invention also relates to a Method of immobilising and/or killing insects, comprising contacting the insects with the liquid pesticidal composition. It also relates to the use of the liquid pesticidal composition to kill an insect or insect population.