The science behind vineyard's bleeding

The reawakening of a Malbec vine in Chacayes, Uco Valley. (Argentina)

As the daylight hours continue to increase this time of year in the Southern hemisphere, the grapevines go through a fascinating reawakening after months of “sleeping.” -Dormancy-

Thanks to the sunlight and warmer days, vineyard soil temperatures begin to rise and osmotic pressure–osmosis being the diffusion of water through the semi-permeable membrane of the vine root cells–builds, causing moisture to get sucked up by the grapevines’ root tips and transported up the trunk to the upper extremities of the vine. From here, this moisture can be witnessed literally dripping (see photo above) as sap from the wounds left by the cuttings during winter pruning. This is the first sign of a vineyard reawakening from its dormant phase throughout the shorter and colder days of the winter months.