Vinpro Technical Harvest Report 2025

Climatic and viticultural trends

General remarks

Vine leaves fell earlier than usual following the harvest, after late outbreaks of downy mildew caused by heavy rainfall in March and April.

The dry growing season resulted in low fungal disease pressure. This favourable weather, combined with effective preventative disease

Rainfall decreased during May and June, while early winter temperatures remained significantly higher than normal. However, rainfall increased sharply from mid-July onwards, and total precipitation for the season ultimately exceeded the long-term average. Temperatures dropped steeply from mid-July, resulting in a cold, late winter for the Klein Karoo. The accumulation of cold units was sufficient to break dormancy, and as such, it was not necessary to apply any dormancy breaking agents. Late-season rainfall also replenished irrigation dams, ensuring producers had an adequate water supply for irrigation. The cold, late winter delayed bud burst, with vines budding two to three weeks later than usual. In general, bud burst was good and even, although initial shoot growth was slow due to cold, wet soils in early spring. However, as temperatures rose, vegetative growth rates increased significantly. Ultimately, the vines grew more vigorously and more evenly than in a typical season. Due to the delayed budding, most blocks avoided widespread frost on 28 August, with only minor frost damage reported. As a result, flowering and fruit set occurred later than usual and under more favourable conditions. Fruit set was notably better than in the previous growing season. Véraison occurred one to two weeks later than usual, with the period being extended and considerable unevenness observed. Early cultivars ripened one to two weeks later than normal, while most late cultivars ripened at their usual times. Although rainfall during the growing season was limited, producers had sufficient water for irrigation, having started the season with full dams and reservoirs.

control, led to healthy canopies and grapes. Although minimal frost damage was reported, a few producers in the Montagu area experienced hail damage (Photo KK 1) . Crop losses were limited, and since the hail occurred before fruit set, there were no subsequent losses due to rot. As a result, grapes could be harvested at the desired sugar levels. The Ladismith area also experienced hail damage during the harvest season. Some producers recorded crop losses, and damaged grapes had to be pressed immediately to prevent further losses. Ultimately, the crop losses were less severe than initially expected. The dry conditions during harvest contributed to healthy grapes and canopies, as well as good sugar accumulation. Although heavy rainfall in late March caused Botrytis bunch rot in some blocks, crop losses were negligible, as the grapes were already ripe and could be pressed without delay.

Photo KK 1: An example of the hail damage observed before véraison in Montagu. Although the canopy was significantly damaged, the impact on crop size was minimal.

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