Vinpro Technical Harvest Report 2025

Climatic and viticultural trends

Weather conditions during the growing season were moderate, with the first high temperatures recorded around 25 December. Canopy growth was vigorous, and some blocks required more than one topping action. Although véraison occurred slightly later than in the previous season, it was still considered within the normal range. Véraison was relatively even, and colour development was excellent. The harvest started 7–10 days later, which was also deemed normal. While the early cultivars ripened later, the later cultivars matured at their usual times. This put cellars under significant pressure during the peak of the harvest. General remarks

The 2024 post-harvest period was characterised by extreme dry and hot conditions. This led to early leaf fall, with some vineyards

already bare by April, which was less than ideal for the accumulation of reserves. Warm and dry conditions persisted throughout June, but from July to August, the region experienced much-needed rainfall and cooler temperatures. Precipitation was especially heavy in July, resulting in total winter rainfall exceeding the long-term average. While cold unit accumulation started slowly in early winter, it had surpassed the previous year’s accumulation by the end of August, setting the stage for even and complete bud burst. The start of September brought a significant rise in daytime temperatures, reaching nearly 30 °C, before dropping below 20 °C due to passing cold fronts. Early spring saw particularly limited rainfall, and nights remained cold, with minimum temperatures consistently falling below 10 °C. Budding occurred about 7–10 days later than usual but was still even and complete. The soil was saturated to field capacity, and farm dams relying on runoff water were at full capacity.

Figure SW 1 illustrates the sudden increase in daytime temperatures on 25 December in the Swartland district. Most grapes had not reached

véraison at that stage, resulting in sporadic sunburn damage in some vineyards (also see Photo SW 1 ). However, the remainder of the season was free from prolonged heat waves. The late winter rains resulted in poor cover crop growth and limited establishment. This, together with the heavy late winter rainfall, complicated weed control efforts. Fleabane and ryegrass

Daily maximum temperature: December 2024 (Swartland)

10 15 20 25 30 35 40 45 Temperature (°C)

0 5

T Max (°C)

Figure SW 1: Daily maximum temperatures in December 2024 in the Swartland district, as measured at Riebeek weather station.

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