COVER CROPS in South African Vineyards

COVER CROPS IN SOUTH AFRICAN VINEYARDS

Tillage has always been central to agriculture. In viticulture, soil tillage can be defined as the management of the soil to maintain the favourable conditions created for grapevine roots by expensive soil preparation. Soil preparation improves the physical properties of the soil to promote root penetration and water infiltration. It may also include incorporation of amendments such as lime and phosphate. Soil management aims to maintain the improved soil physical conditions created by effective soil preparation. Goals include eliminating weeds, increas- ing organic matter, limiting compaction, preventing erosion, and optimising water use.

Mechanical tillage is one method for managing soils. However, mechanical tillage disturbs the soil, which can have negative effects on soil health and the physical structure of the soil (Figure 1.1). These impacts include loss of soil organic matter, reduced soil biodiversity, increased erosion, loss of water-infiltration capacity and, to a lesser extent, reduction of water-holding capacity.

MECHANICAL TILLAGE CAN HAVE NEGATIVE EFFECTS ON SOIL HEALTH AND THE PHYSICAL STRUCTURE OF THE SOIL.

FIGURE 1.1. Irresponsible cultivation has compacted the soil in this full-bearing vineyard, leading to restricted grapevine root growth. (Photo: ARC Infruitec-Nietvoorbij).

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