COVER CROPS in South African Vineyards

COVER CROPS IN SOUTH AFRICAN VINEYARDS

TABLE 10.1. Recommended sowing rates for cover crops. Adapted from Fourie et al (2001). Cover crop Sowing rate in kilograms of seed per hectare Grasses 100 Grazing vetch 50 Bur and snail medics 25 Pink serradella 25 Caliente 10 Canola 8 White mustard 8 Nemat 5 Certified seed is preferable, as it has been cleaned and the seed company will vouch for its specified germination percentage. Order four to five months in advance to avoid disappointment. Legumes can be sown during the first three seasons on all soil types to increase nitrogen levels. On sandy soils, legume cover crops can be continued until nitrogen fertilisation of the grapevines at full bloom is no longer necessary.Thereafter, legumes should be rotated annually with a grass to avoid excessive vegetative growth of the grapevines. On sandy loam and sandy clay loam soils, legumes and grasses should be rotated annually from the fourth season onward to avoid excessive vegetative growth of the grapevines. On fertile soils, rye or triticale can be rotated with oats. Rotation will also help prevent a build-up of diseases that affect a specific cover crop.

JOHAN FOURIE

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