FERTILISER GUIDELINES FOR THE WINE INDUSTRY

FERTILISATION PROGRAMME FOR NITROGEN

According to international and local research it is currently accepted that about 4 kg/ha -1 N per season is required for the production of 1 ton grapes. This can serve as guideline on low to moderate vigour soils, but in practice it cannot be generally applied. There are however, differ ent approaches that can be used for establish ing realistic N-fertilisation programmes. VIGOUR There is a strong demand for N by leaves, shoots and green bunches during the early growing season, and a second peak demand just after harvest, when N is primarily stored in shoots and roots. The vine uses this N during and after bud break, when the soil is still cold and the roots inactive. On the strength of this, N-fertilisation is applied in three instalments – about 1 month after budding, then again after flowering or at pea berry stage, and finally just after harvest. Vigour serves as guideline accord ing to which this basic maintenance programme can be adjusted, as set out in Table 8.

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