COVER CROPS in South African Vineyards

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SHUTTERSTOCK

EFFECT OF COVER CROPS ON GRAPEVINE NUTRITION AND PERFORMANCE

In these trials, nitrogen in the leaf petioles was measured as nitrate-nitrogen.According to research by Conradie (1994), levels below 300 milligram per kilogram are considered seriously deficient, and levels below 700 milligram per kilogram represent a slight undersupply. Nitrogen fertilisation at grapevine berry set is not necessary when nitrogen measured as nitrates in the leaf petioles of grapevines exceeds 1 000 milligram per kilogram.

This chapter discusses the interactions of cover crops and their mulches with grapevine nutrition and performance. Nitrogen levels in the grapevine leaf petiole and grape juice are discussed, as are vegetative growth and grape yields. Trials were conducted in the Coastal region, Breede River valley, Lower Orange River region, and Olifants River valley. Also included in this chapter are the results of root distribution trials performed in the Breede River valley.

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