Technical Yearbook 2024

Aerial photo: The Sentinel-2 satellite image of 26 September 2023 in the Olifants River with vineyard blocks indicated in red and the flood line in blue.

with the first heat in August. This obviously made fungal control difficult, as the soil was still too wet for tractor traffic. Consequently the important first fungal spray applications of the season were often applied too late and this heightened the risk for downy and powdery mildew. Floods during the growing season: observations from 2023/24 Unfortunately the 2023/24 season’s floods were not only limited to the winter period. Widespread rain during the second half of September meant that approximately 1 100 ha of vineyard, including the canopy, were again submerged by the end of September. This represents about 14% of the area’s vineyard surface. By this time many Colombar, Chenin blanc and Ruby Cabernet vineyards were already at the 30 cm shoot length growth stage. There were also cultivars like Hanepoot which had not yet budded, as well as blocks that were in the process of budding and blocks that only reached 10 to 20 cm shoot length before the flood came. As the growth stages of the different affected blocks were so varied, along with other variables like cultivar, location, time under water and the age of the blocks, it was difficult to determine the damage. We were however able to record a few observations for future reference.

This bushy appearance of the hardest hit blocks was observed by the end of December 2023.

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TECHNICAL YEARBOOK 2024