This invention relates to dry, water soluble, pesticidally acceptable particulate compositions, to a method of use thereof for killing or controlling pests including weeds and to a process for preparing such compositions. This invention also relates to dry, water soluble and/or water dispersible, pesticidally acceptable particulate herbicidal compositions containing one or more herbicides, a herbicidal method of use thereof and to a process for preparing such compositions. The dissolution or dispersible rates of particulate pesticidal compositions in water are enhanced by the presence of a small but effective amount of an organosilicone block copolymer wetting agent or a fluorocarbon wetting agent.