Some Bordeaux estates lit candles in their vineyards at the end of last week, after authorities warned of potential frost damage.
Wineries in northern Burgundy, including those in Chablis, were also forced to take precautions in some areas.
Early reports suggested no major damage so far, but producers faced more anxious waiting, amid forecasts of low and freezing temperatures mid-week. Severe frost can damage potential production, if buds are affected.
‘It’s stressful,’ said Guillaume Willette, director of the Burgundy wine appellation union, Syndicat des Bourgognes. ‘We will have more visibility early next week.’
Véronique Drouhin-Boss, head winemaker at Domaine Drouhin, said that the team has used protective water sprays on vines in the Bougros grand cru in Chablis for two consecutive nights, but this anti-frost method hasn’t been needed in other grands crus yet.
‘The rest of the vineyards have been equipped with candles, but so far they have not been lit. Tomorrow (Wednesday 1 April), there is a frost warning again, which could require that we light them.’
Drouhin has thermometers in its vineyards that set-off an alarm at the vineyard manager’s home if temperatures fall too low.
Cécile Mathiaud, of the Burgundy wine council, BIVB, said that budding hasn’t finished in most areas, lowering the immediate risk.
Winemakers were staying positive, she said. ‘Tomorrow could be another tricky day (0 to -2 degrees) but the rest of the week shall be warmer.’
In Bordeaux, wine union leaders told Franceinfo that they weren’t aware of major damage as yet, but all eyes were on the next few weeks.
Château Croix de Labrie, the St-Emilion grand cru estate, posted a video on Facebook of how it is installing candle burners across its vineyards.
Bud-break was relatively early in some parts of Bordeaux, due to a mild winter, and producers remember the late April frosts of 2017, in particular, which severely hampered production for that vintage in some areas.
Authorities in Bordeaux reminded châteaux that vineyard candles should only be lit if the frost risk is ‘proven’, and must be monitored at all times.
Vineyard workers must also abide by the social distancing rules introduced to reduce the spread of coronavirus, or Covid-19.
In Burgundy, Drouhin-Boss said the situation was a marathon for wineries, rather than a sprint. ‘We are at risk until 12 to 15 [of] May. So the road is still long.’
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(Jane Anson, February 2018)