A method for the control of soil-dwelling pests and/or soil-borne diseases comprising treating a plant propagation material with an effective amount of the pesticidal composition and/or applying an effective amount of a pesticidal composition to a locus where control is desired, provided that the composition comprises, as active ingredient, one or more pesticides (A) having a water solubility of at most 100 μg/liter, at 25° C. at neutral pH, and at least one formulation auxiliary, wherein the size of particles in the composition is in the range 3.60 μm to 0.70 μm at X90. Abamectin has been found to be particularly effective against nematode damage.
