This is produced by heating pure, ground sulphur and then crystallising in cold water. By mixing it with water, a homogeneous, sprayable suspension is formed very quickly. So-called wetting agents are added which, when dissolved, reduce the surface tension of liquids so that they can penetrate more easily into the interior of solid materials. This is where the name "wetting sulphur" comes from. This is sprayed in the vineyard as a preventive measure against fungal diseases, especially scab and powdery mildew. The sulphur particles thus deposited on the leaf surfaces of the vines form sulphur dioxide, which also acts quickly against mites, for example, through the action of moisture, light and oxygen. See also sulphurisation and sulphurous acid.
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Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)