Guidelines for the preparation of table grapes in SA for export 2025/2026_ND

The principles of pruning

Why prune? Pruning is the start of the new season. In table grapes, unlike in wine grapes, precision pruning is vital. Pruning is the first phase of crop control. A vineyard that isn’t pruned develops shoots, but the shoots grow weakly and break bud unevenly due to competition. Therefore, many bunches are carried on weak shoots. The result is smaller berries, delayed ripening, poor colour, and, worst of all, poor shelf life. The aim of pruning is to carry bunches on vigorous shoots and to ensure bunches are spread evenly over the entire bearing surface. In table grapes, bunches mustn’t be in contact with each other. Avoid gaps in the canopy where canes don’t cover the surface. Ideally, all shoots bearing bunches must be equally vigorous and approximately 80–120 cm long at flowering. Bunches shouldn’t be carried on shoots that are shorter than 50 cm, as these bunches take longer to develop sugars and colour, their cells break down, and the result is browning and poor shelf life. The timing of pruning determines the harvest date. The period between pruning and harvest varies by region and cultivar, but the average is approximately 142 days. This can be considerably shorter in very warm and early regions or with early cultivars. In subtropical areas (15° North or South of the equator), such as parts of Peru, Brazil, and India, grapevines do not enter dormancy. So, the time of harvest is regulated by adjusting the pruning date and other manipulations. Definitions of bearers Grapevines bear on one-year-old wood on two-year-old wood. A spur or short bearer has two buds. Don’t count the collar buds around the base of the cane. A half-long bearer has 6–8 buds. When applying a half-long-bearer system, leave a short bearer near the base of each half-long bearer. The short bearer is for renewal in the following season. A long bearer or cane has 12–14 buds. When applying a long-bearer system, leave a short bearer near the base of each long bearer. The short bearer is for renewal in the following season.

12 SATI GUIDELINES FOR THE PREPARATION OF TABLE GRAPES IN SOUTH AFRICA FOR EXPORT