What does wine dormancy and the winter season have in common?
For those of us who celebrate daylight savings, it comes to an end this Sunday the 4th. Getting up in the mornings will be harder, and driving home from work will begin to occur under the blanket of darkness illuminated by white headlights, red taillights, and yellow street lights.
Winter is coming…
This is the time of year when we as people begin a hibernation state, if you will. But we aren’t the only ones! The vines will begin their dormancy state too.
During the winter months, the shoots of last years growth will be pruned as the leaves have fallen and the energy will be transferred to the woody trunks; away from the last seasons canopy growth. This is a very important time for the vine. It will begin storing all the energy it will need for the spring when warm temps will wake the vine up and start the bud break process.
*sings “The circle of life…”*
It is important for the vines to get a good rest, but sometimes mother nature has other things in mind (anyone remember the Christmas Massacre of 1980?). Sometimes December/January temperatures will reach into the 70°+ range in certain microclimates which can trick the vines into believing it is later in the season than it actually is. This can affect the vines adversely and ruin entire vintages if the temps continue for extended periods of time.
It is a common misconception that areas who see winter snowfall have vines that fully shut down. That is not the case, the vines are always awake in the trunks, and it is important to know that the roots continue to grow and mature just after harvest and into the beginning of winter to assist with the vines holding of carbohydrates internally to protect itself when outside temps drop below 32° and water freezes. If a vine doesn’t have enough carbohydrates, it to can completely freeze through and cause cold injury or trunk injury.
Vitis vinifera tends to be more susceptible to cold damage from low temperatures or sudden drops in temperature, and winemakers in areas where this occurs frequently have methods to assist in protecting the vines during this time period.