A cotton seed coating composition, in the form of particles, comprises at least one organic material selected from waxes having a melting point of at least 50°C； and at least one additive for enhancing seedling growth and/or vigour from cotton seeds, the additive being an inorganic material and/or a live biological agent. The wax may be carnauba wax, beeswax, chinese wax, shellac wax, spermaceti wax etc., and the particles can have a mean volume diameter of at least 5 micron. Preferably, the organic material is applied to cotton seeds in a dry powder form. A method of coating cotton seeds with the coating composition comprises obtaining a population of particles of wax admixed with additives, wherein the particles are of a pre-determined volume mean diameter； and applying the population of particles to cotton seeds. The method may comprise heating the organic material to produce a liquid or gas, cooling the liquid or gas to below its melting point to form a solid, adding the additive(s), and machining the solid organic material into particles for subsequent application. Alternatively, the additives may be added to the heated organic material before cooling.
