The vineyards of northern Italy have been burning bright this week as winemakers light thousands of torches across the slopes. But why? It's an enterprising solution to a perennial problem: the weather. As frost and snow returned unseasonably late to swathes of the north, winemakers sought to protect their vines from subzero temperatures, which can wipe out tender new growth where grapes are just starting to emerge.

"Any more than one degree below zero and you're really in trouble," winemaker Andreas Huber told Ansa from Alto Adige (South Tyrol), where temperatures of between -3 and -9 degrees C were recorded on Wednesday morning. Seeing the forecast, he and other winemakers prepared by positioning hundreds of "anti-frost" torches every few metres throughout their vineyards, setting them ablaze as the mercury started to fall.