There are many steps in maintaining and growing wine grapes, but Aurora Cellars goes a step further to help give our reds a unique advantage. In recent years, we have introduced the practice of using mylar foil in our vineyards. We are the only winery in the area to use this practice in our vineyards.

Mylar is a reflective plastic polymer with the appearance of aluminum foil. It is described as being food safe and substantially lighter and more flexible. 

Mylar foil isn’t a common practice in the grape industry. 

Aurora Cellars adopted the idea from our neighboring apple growers who use the practice on their Honeycrisp Apple trees. “Since this process is used to develop the color desired on the market, it just made sense for our vineyard crew to try and see how our grapes took to it,” explains Head winemaker, Drew Perry.

While everything we do in the vineyards helps the vines and grapes in some way, using mylar foil has a few effects – in theory. 

One of the effects it has is by helping control and suppress the weeds where it is laid. It also reflects light up into the canopy of the vines and once it is in the fruit zone, temperatures increase in the canopy and accelerate the drying out of the morning dew.

As the temperature increases in the canopy, the fruit is getting more light – which is needed for the grapes to reach their full potential before harvest. “The skins are rapidly developing and going through veraison,” says Perry.

Veraison is a growing phase when the color of the grape skin changes and berries begin rapidly accumulating sugars. The goal of the extra exposure is so the skins on the fruit can thicken and increase the anthocyanin.

Viticulturists hope this process leads to greater color intensity and the potential in the final product – wine.

Michigan is a cool climate wine growing region. Due to the cold springs and warm fall weather the state experiences throughout the year, the grapes benefit from the longer growing season which allows us to get the most out of the fruit.

Perry explains the practice of using the mylar foil would be useful to cool climate regions that need more intense sunlight during the development stage. If it was used in other warm climate growing regions, the process would accelerate sunburn issues on the fruit and exacerbate drought stress.