Vineyard Essentials: Spring Pruning and Tying Techniques
Spring frosts are a perennial concern for UK grape growers. Various frost protection tools are available, including gas burners, bougie candles, giant air-moving fans, water sprinklers, and solutions that use advanced technology like Frolight’s infrared frost protection system. Vineyard owners can also mitigate frost damage through strategic pruning techniques that delay bud development, giving vines a better chance of surviving late frosts.
Frost damages young green tissue on grapevines by either bursting cell walls with expanding ice crystals or dehydrating cells osmotically. Dormant buds, protected by their outer shells, are far more resistant than tender, growing shoots. So, delaying budburst in primary canes until after the frost risk has passed is key.
Pruning Strategies for Frost Protection
Pruning is critical, as poor choices can damage vines and impact yield. Buds furthest from the crown tend to burst first. While pruning at the last possible moment before budburst can help, this is often impractical for larger vineyards. Instead, two techniques can be effective: double pruning and leaving sacrificial canes.
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Double Pruning: This technique is particularly effective for spur-pruned vines and can even be mechanised for efficiency. The first pass, performed in winter, involves cutting shoots back to 30 - 45 cm above spur height. The second pass, carried out as late as possible, refines spur and bud selection. An added benefit of this method is the reduced risk of Eutypa infections.
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Sacrificial Canes: For Guyot-pruned vines, a similar approach can be used by initially leaving longer canes and trimming them later. Leaving sacrificial canes standing upright helps delay budburst in the primary canes. First, select and tie down the primary fruiting canes. Then, choose the sacrificial cane, but leave it untrimmed and upright. Once the risk of frost has passed, assess any damage. If the buds on the primary canes remain unscathed, remove the sacrificial canes entirely. If frost damage has occurred, assess and remove a primary fruiting cane if not enough viable buds have been retained. The sacrificial cane can then be tied down to maintain bud numbers and ensure a good crop.
Tying Down: Timing and Technique
Tying down is a labour-intensive, but crucial vineyard task. It defines the vineyard’s structure, promotes even budburst, balances shoot growth, maximises sunlight exposure, improves air circulation, reduces humidity, and ultimately enhances yield and grape quality.
Ideally, tying down should be done as vines exit dormancy and sap begins to rise. At this stage, canes are more pliable and less prone to snapping. If done too early, brittle canes may break, reducing yield. Delaying too long can lead to uneven budburst and erratic shoot growth, affecting the entire season’s development. A common method is to leave one sacrificial cane standing while tying down the primary fruiting cane. If frost later damages the tied-down cane, the sacrificial one can serve as a backup. If no damage occurs, the sacrificial cane is simply removed. While this technique offers protection, it also adds time and labour costs, which is a key consideration.
Tying down can be done using hand ties or handheld binders. Hand ties are simple, cost-effective, and biodegradable, allowing experienced workers to secure over 800 vines daily. Handheld binders, available in electric and manual versions, are faster than manual tying. Electric models, such as Ligatex and La Cruz, improve efficiency, with some using biodegradable ties.
Skilled Vineyard Labour: The Backbone of the Industry
Pruning and tying down may seem like simple tasks, but they require skill and experience. Poor pruning decisions can wound vines and reduce yield, while improper tying down can delay budburst and impact vine health for the season. While some vineyard owners handle these tasks themselves, hiring experienced labour teams ensures speed and precision in executing these time-sensitive jobs.
Vineyard workers are the unsung heroes of the industry, enduring all weather conditions to perform demanding physical tasks that directly influence the vineyard’s productivity. The annual WineGB National Pruning Competition celebrates the skills and expertise of these workers. This year’s competition will be held at Clayhill Vineyard on March 7th.
Event organiser James Dodson of VineWorks explains, “The competition is a fun way to acknowledge the incredible contribution vineyard workers have on supporting our industry. Becoming a proficient pruner takes years of practice - it’s a physically and mentally demanding job where each vine must be assessed individually. Less experienced pruners take longer and make mistakes. Recognising the contribution our vineyard workers bring to the quality and reputation of the UK wine sector is important.”
VineWorks is a leading viticulture services company having established over 300 vineyards across the UK.
