FERTILISER GUIDELINES FOR THE WINE INDUSTRY

IN CONCLUSION A fertilisation programme for a vineyard block, or the levels at which certain nutrients are fertilised as single elements or in combination, thus depend on a few important factors, namely: THE SOIL TYPE: • This is determined by the soil chemistry and pHdeficiencies, which should already be corrected and supplemented during soil preparation. • The soil structure and texture determine the drainage ability or leaching potential of the soil – stony and/or sandy soils are more subject to leaching losses and the choice of fertiliser type as well as application levels should be adjusted compared to soils with higher clay percentages. • The percentage carbon and organic material content of the soil determines inter alia the microbe life as well as the mineralisation ability of the soil, i.e. the ability of soil to make nitrogen available to the grapevine. A soil with a high % C and organic material requires significantly less nutritional supple ments, as indicated in Table 9. PRODUCTION LEVELS AND ACCOMPANYING WINE OBJECTIVE It is very important to know for which wine objective/end product the specific vineyard is being managed – premium/quality wine or bulk wine? For pre mium/quality wine objectives, viticulturists and winemakers prefer vineyards with average to slightly lower vigour which are naturally in balance with lower

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