Pardon the overused GOT reference but very few people dread a long winter more than John Snow and winemakers in cold climate areas.
Winter frost, also known as Nature’s way of telling grapevines to ‘chill out’,” can be a real pain in the bud for vineyards. Not only can it damage or kill the buds that will produce the grapes for the upcoming growing season, but it can also make winemakers want to cry into their glasses of Merlot.
The dangers of winter frost to grapevines are many and varied. For example, a light frost may only damage the buds, leading to a smaller grape yield for that year. But a severe frost can outright kill the buds, leading to a complete loss of the grape crop for that year and potentially a few more years.
Another danger of winter frost is the potential for “frost cracks” (Also known as Gélivures) in which the water and sap in the vines expands and bursts the bark, leaving the vine open to disease and pests. This can be especially damaging to older vines, who are already at the end of their rope and can’t handle any more stress.
Additionally, winter frost can also damage the vine’s root system, making it harder for the vine to absorb water and nutrients. This can lead to weaker, less productive vines in the future. So, not only do you have less grapes to make wine, but the quality of the grapes that survive may be lower as well.
To protect against winter frost, winemakers have a few options. One method is to use wind machines, which mix the warmer air above the vineyard with the colder air at ground level, preventing frost from settling on the buds.
Another method is to use smudge pots, which burn oil to create heat and prevent frost from forming. However, these methods can be costly and may not always be effective. Heaters and Over-vine sprinklers can also be used and although they are very costly, they can save the entire production. When water is sprayed and freeze around green tissues it releases heat and thus protects vines.
Some winemakers also choose to plant grapevines that are more cold-hardy, such as Riesling or Pinot Noir. These grape varieties can handle colder temperatures better than others, and are less likely to be damaged by winter frost. But even with these precautions, Mother Nature can still be unpredictable and there is no 100% guarantee against frost. For some good examples available in Hua Hin of Riesling and Pinot Noir produced in cold climates where frost is a hazard you can look for the DOMAINE WACHAU Riesling Federspiel Terrassen or the DOMAINE FAIVELEY Chambolle-Musigny.
Despite the dangers of winter frost, winemakers know that it’s all part of the game. After all, making wine is a labor of love and you can’t make great wine without a little bit of risk. And let’s be real, if it were easy, everyone would be doing it. But the satisfaction of a great vintage and the taste of the wine, makes it all worth it in the end.
So, let us raise a glass to the dangers of winter frost and the hardworking winemakers who brave it all to bring us the delicious nectar of the gods.