Rendering gel coating on seeds that has been solidified by the action of metal ions easily disintegratable comprises blocking the insolubilising action of the metal ions with a sequestering agent. The gel coating pref. comprises sodium alginate, sodium polyacrylate, or guar gum, hardened with metal ions. The sequestering agent is preferably sodium or potassium tripolyphosphate, sodium or potassium hexametaphosphate, polycarboxylic acids and hydroxy carboxylic acids. These are incorporated into the gel in microencapsulated form, the encapsulating agent being thermally reversible, such as gelatin, carragheen, or higher fatty acid esters. In use the gel-coated seeds are heated to above the stable temperature of the encapsulating agent, by hot air or water, and immediately mechanically sown. The breakdown of the gel after the physical handling of the seed has ceased.
