VINES AND FROST: “VINEYARD ITALY” IS NOT AT RISK AND SNOW IS A NATURAL WATER RESERVE, SAY THE AGRONOMIST LEONARDO VALENTI (UNIVERSITY OF MILAN) AND ATTILIO SCIENZA, ONE OF THE TOP EXPERTS ON VITICULTURE IN EUROPE

Temperatures have been constantly below the freezing point - a shivering start for February. Alarms have rung out that the icy cold would compromise many Italian farm products. But, are vineyards at risk? At first look, it seems vines are an exception. Winenews asked two of the top experts on Italian viticulture who both basically sent the same reassuring confirmation: “These temperatures are not a problem for vines,” explains Leonard Valenti, professor of viticulture at the University of Milan, “it would take much more constantly lower temperatures, around 15 C degrees below zero, to put vines in a dangerous situation. Plus, the cold temperatures arrived when the physiological activity of the vines was completely at rest. Maybe in the Trentino region there could be some risk for vineyards at very high altitudes, but again, if the plants are at rest, the risk is very low”. “It is very unlikely,” says Attilio Scienza, one of the leading experts on viticulture in Europe, “that vines will be damaged by this cold. If temperatures dropped to below 15°C and stayed there for a long time, then the plants would be at risk. But there are some exceptions and some advice: these icy cold temperatures could damage the weaker vines, that is, the ones that produced high quantities last harvest and have low starch reserves; there are some vines that are more sensitive to low temperatures and they might have some difficulties. Clearly, absolutely no pruning vines during these extreme temperatures.”
A totally positive and extremely important fact considering that autumn and winter were essentially dry is the snow, which is a cure-all and makes us think we will not have problems with water during the next harvest. Where abundant snow has fallen, a half meter and more, it will have a beneficial effect and is the ideal answer to an essentially dry autumn and winter,” continues Valenti “the soil will be an important water reserve, which will penetrate slowly and not be wasted”.
Snow is a natural thermal insulator,” Scienza continues, “and stops ground temperatures from dropping, which could have a negative effect on the most delicate part of the vine, its roots. And, snow is a way to let water seep slowly into the ground. Considering that more or less one millimeter of water equals one centimeter of snow, we are talking about an enormous amount of water that the ground will absorb, without wasting any”.
In the past, have cold temperatures been dangerous to “Vineyard Italy”, and if so, when? “ Historically, the last freeze that created difficulty for vineyards, but mostly for olive groves was in 1985,” said Professor Scienza. “Going back in time the freezing temperatures in 1929 and 1930 were devastating, but at that time farmers used to inter vines in special pits that were then covered over with earth (this method is still used in Armenia) thereby avoiding total disaster”.