As spring begins its slow transition into summer, we’ll watch our vines accelerate to their maximum growth rate just before flowering. This is an important time to start the summer-long process of managing the canopy of the grapevines. The process begins with the removal of unwanted shoots from the vine’s head or cordon(s). Their removal can significantly improve our grape quality, and thus wine quality. Here is the story behind shoot thinning.
What is a shoot?
A shoot is the new growth of a grapevine that develops from a bud; it consists of a stem, leaves, tendrils, and potential grape clusters.
Why are some shoots removed?
Typically, shoots chosen for removal are those that are either, not fruitful or are less fruitful than others (like water shoots, basal bud shoots and lateral shoots). A major benefit of thinning is the reduction to the density of the vine’s canopy; this allows both sunlight and airflow to infiltrate through the canopy reducing potential fungal growth. Another factor taken into consideration is a shoot’s position. Shoots with superior vertical angles (towards the trellis wires) are typically kept over shoots heading in an inferior direction; this prevents possible cluster-shading later. Lastly, by removing excess foliage and potential grape clusters, we lower each vine’s yield, allowing them to focus their energy on the fruit and foliage that is left on the vine (producing a more concentrated grape).
How are the shoots removed?
Shoot thinning is normally done by hand once they have reached roughly eight inches long and grape clusters have started to develop. It is at that length that the discrimination can be made about their position and fruitfulness. The unwanted shoots are then broken off, dropped to the ground, and later tilled into the soil.
Just like everything we do out in the vineyard, the aim of shoot thinning is to increase the quality of our fruit and, in the end, make some tasty vino.
Cheers, Rubin - Vineyard Foreman
Posted on: Jun 6, 2011