FERTILISER GUIDELINES FOR THE WINE INDUSTRY

production levels and also have a lower nutritional requirement. In the case of higher producing bulk wine vineyards it is essential for vineyards to be more vigorous with subsequent higher nutrient levels. THE REGION Regions with higher rainfall and especially on certain soil types where there is a greater leaching potential, require more instalments and higher fertilisation application levels. The same applies for areas where intensive irrigation prac tices are followed compared to dry land vineyards or where only supplementary irrigation is given on high potential soils with high water retention abilities and less fertilisation can be applied. OTHER POSSIBLE DETERMINING FACTORS ARE, FOR EXAMPLE: • Vineyard age – old vineyards with deep and elaborate root systems are well buffered and “look after themselves”, and therefore require less fertilisation. • Certain cultivars and rootstock combinations can result in very strong vigour where fertilisation can be decreased, e.g. Sauvignon blanc; Cabernet; Shiraz; Colombar on Ramsey/R99/US 87 rootstocks. Consequently, generalisations/standard fertilisation programmes for all sit uations must be guarded against and all the above-mentioned factors must be considered in the determination of a fertilisation programme for a specific vineyard block. It is imperative that the producer, soil scientist and viticulturist, the winemaker and the fertilisation expert and/or agent are all synchronised with the situation and the wine objective for which the specific vineyard block are managed.

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