Vinpro Technical Harvest Report 2026

General remarks

The season progressed smoothly, with favourable weather conditions and low disease pressure prevailing until November. Producers consequently adjusted their fungicide programmes to reduce the number of spray applications. However, December, January and March experienced more humid mornings, together with light rainfall during the harvest period (Figure OL 3) . This led to a significant increase in Aspergillus incidence in Chenin Blanc vineyards in the area, with sour rot also becoming problematic later in the season. Notable progress was, however, achieved with the Fruit Fly Baiting Project, which resulted in late Colombar and Hanepoot grapes remaining green and healthy until the heatwave of 8 March.

Photo OL 1. Colombar bunches showing good fruit set.

Photo OL 2. Botrytis rot on Sauvignon Blanc developing into noble rot.

Leaf wetness index (2024 –2025 vs 2025–2026)

30000

25000

20000

15000

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0

Sep

Oct

Nov

Dec

Jan

Feb

Mar

Minutes 2025–2026 Minutes 2024–2025

Total leaf wetness duration (minutes)

Figure OL 2. Year-on-year comparison of total leaf wetness duration (minutes) per month (2024–2025 vs. 2025–2026), Vredendal, Olifants River.

VINPRO TECHNICAL HARVEST REPORT 2026 36