Abstract: A method of injecting grout into soil using a combined injection and boring rod wherein the rod comprises a tip and at least one injection nozzle at the lowermost end thereof. A sleeve packer of an elastomeric material is embedded in a recess in the periphery of the rod along the length thereof. A plurality of passages extend in and along the rod, the passages being defined by at least two parallel inner tubes spaced within an outer tube, and further by the spacing between the outer tube and the inner tubes. The method includes the steps of inflating the sleeve packer by introducing fluid pressure into the recess through a hole in the outer tube communicating with one of the passages, feeding two liquids of curable grout through respective passages and mixing the two liquids within the rod at the tip of the rod, and then injecting the mixed grout into the soil from the injecting nozzle.