COVER CROPS in South African Vineyards

COVER CROPS IN SOUTH AFRICAN VINEYARDS

Vegetative growth and grape yield Shoot mass and grape yield for the annually sown cover-crop treatments are shown in Figure 8.5 and for those sown two-yearly, as well as for perennial dwarf fescue, in Figure 8.6.

Shoot mass did not differ significantly between treatments. Grape yield in 1996/97 was significantly higher in all the annual cover-crop treatments than in the perennial dwarf-fescue treatment.Yields were also significantly higher in 1996/97 in the treatment with two-yearly rotation of grazing vetch and triticale than in the treatment without a cover crop. In 2001/2002, there were no significant

SHOOT MASS DID NOT DIFFER SIGNIFICANTLY BETWEEN TREATMENTS.

differences in grape yields between the cover-crop treatments and the control. Competition between perennial dwarf fescue and grapevines seemed not to impact grape yields on these relatively fertile soils. mix annual rotation

18,00

16,00

14,00

12,00

Shoot mass 1996/97 Shoot mass 2001/02 Grape yield 1996/97 Grape yield 2001/02

10,00

8,00

6,00

4,00

Mass in tonnes per hectare

2,00

0,00

Triticale Grazing vetch Rye|faba bean Triticale|vetch No cover crop mix annual rotation

FIGURE 8.5. Vegetative growth and grape yield in annually sown cover-crop treatments compared to a control in the Breede River valley. Adapted from Fourie (2011).

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