FERTILISER GUIDELINES FOR THE WINE INDUSTRY

Manure Large amounts of chicken manure, especiallly broiler chicken manure, are annually used by grapevine farmers. Cow manure and layer hen manure are also used however. Although the NPK-composition of the respective manure types is relatively constant, it is recommended to regularly request analyses from the supplier. Application amounts should be managed according to the composition of the manure and the nutritional requirements of the vineyard, as well as the soil characteristics. The generally accepted norm is that 50% of the nutrients is released during the first year after application. For the remaining nutrients cycle is then repeated in the following years. Cultivation practices, soil temperature and moisture will have an impact on the amount of nutrients that are released. The best time to apply manure is in in the post-harvest periods, or as a source of nutrients for the cover crop. In this way the release of nutrients are managed optimally. Producers must be wary of excessive applications and/or long-term applica tions – as mentioned above, it leads to a build-up of P, K and micro-nutrients that can induce imbalances in nutrient uptake. Furthermore, decomposition of and N-mineralisation from these materials lead to pollution of sub-soils and subterranean water. Pelleted manure (mainly chicken manure) usually has similar nutrient concen trations as loose manure. Because it handles easily and can be accurately applied, it is managed better and used in a similar way as fertiliser. Various brand names are marketed, e.g. Rescue, Neutrog, Enhancer. Compost As compost can be produced from a wide variety of raw materials, the con centration and composition of the nutrients therein can also vary significantly. It is therefore recommended to request an analysis of the product when it is purchased. The production process plays an important role in the quality of the product. If it is not managed well there is a risk that the process has not been completed and that the C:N-ratio of the compost is consequently too high (>30:1). If you do not have an abundant source of raw materials at your disposal, compost is generally cheaper to purchase than to prepare yourself. If grape skins and pips or other organic material like wood chips are available, consider applying it immediately in the vineyard instead of composting it. Composting is a natural breakdown process of organic material and it will take place in the vineyard if the correct conditions are created and maintained. Applications

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