A warm spring with a lot of rain has resulted in the growth of a mildew fungus which is proving to be a threat to sherry production in Jerez region of Andalusia.
Wine producers are apprehensive that as much as 80% of the grape harvest could be lost.
Vineyard owners around San Lúcar report concern that the damage could hit between 50% and 70% of growth and around Trebujena damages could be between 30% and 60%.
"After a dry and mild winter no-one expected the heavy rainfall during May," said Francisco Guerrero, head of the Jerez growers cooperative.
"Many growers hoped to make savings where they could and hadn’t taken preventative measures against such unusual weather," he added.
Sherry producers have been making inroads in recent years in overcoming sherry’s image as a drink for elderly people and making it more attractive to younger drinkers.