Handbook for Irrigation of Wine Grapes in South Africa

Chapter 9

9.6 CONCLUSIVE REMARKS Growers and technical advisors should understand the different ways in which sub-zero air temperatures could damage vineyards, particularly in early spring after budbreak. Growers have to make an effort to predict the risk of cold damage, as well as whether it will be a freeze or frost. The latter will determine what precautionary measures, if any, will be applicable. Growers need to adapt viticultural and tillage practices to minimise the risk of cold damage, i.e. prevention is always better than cure. Although overhead sprinkler irrigation is most commonly used to prevent frost damage, it might put already limited water resources under pressure in some grape growing regions. Heaters or wind machines seems to be useful alternatives, particularly in areas where the risk of cold damage is high. Furthermore, combining heaters and wind machines provide more energy efficient protection against cold damage. Technical advisors and growers are encouraged to carry out pilot studies regarding vineyard management practices following cold damage. Ideally, their findings and observations should be combined to enable better interpretation and understanding.

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PHOTO: P SNYMAN.