Abstract: An apparatus for the injection of liquid additives, such as fertilizers and insecticides, into irrigation sprinkler systems for even dispersal within the least distance of conduit pipe from the point of injection is presented. Said injection is accomplished by injection of the additive through a hollow L-shaped spindle about the horizontal arm of which is a rotatable hollow hub from which extend hollow injection tubes, along the length of each there being a semi-circular impeller blade. The apparatus, centrally located within the conduit pipe of an irrigation system, disperses pressure-injected additive while the rush of water through the conduit causes the impeller to rotate, thus further facilitating dispersion of the additive.