COVER CROPS in South African Vineyards

COVER CROPS IN SOUTH AFRICAN VINEYARDS

Woogenellup subterranean clover

2,32

Black oats Overberg oats Dwarf fescue Weeds Pink serradella Rye Grazing vetch Paraggio bur medic

2,45

2,75

2,95

3,16

3,35

3,45

3,55

3,74

2,00

2,50 3,00

0,00 0,50 1,00 1,50

3,50

4,00

Dry matter in tonnes per hectare FIGURE 3.20. Average annual dry-matter production of all cover crops in vineyard trials in the Lower Orange River region. Adapted from Fourie (2005).

Which cover crops were successful? Average annual dry-matter production for all the cover crops in the long- term vineyard trial is illustrated in Figure 3.20.The average dry-matter pro- duction of the natural weed stand is given for comparison. Based on both dry-matter production and weed suppression, the cover crops for this region are ranked as follows: 1. Paraggio bur medic 2. Grazing vetch 3. Rye Although the perennial dwarf fescue produced more dry matter than either black oats orWoogenellup subterranean clover, the perennial grass suppressed weeds less effectively than black oats andWoogenellup subterranean clover. As for other regions, cover-crop rotation is recommended. Reference list Fourie JC. 2005. Cover crop management in the vineyards of the Lower Orange River region, South Africa: 1. Performance of grass and broadleaf species. South African Journal of Enology and Viticulture , 26(2), 140–146. 4. Pink serradella 5. Overberg oats 6. Black oats 7. Woogenellup subterranean clover.

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