By Joel Jorgensen, Vineyard Manager at Veraison ltd.
There is no substitute for good old-fashioned ‘boots on the ground’ crop walks, inspecting the vines and gathering data to enable informed decision making. At Veraison we aim to time our vineyard walks around each vineyard’s growth stages and ensure that every intervention made is based on vineyard data, insight, and experience.
We are lucky enough to see vineyards of all shapes and sizes on a day-to-day basis and at different times of the year there are certain themes of advice or questions we are asked. Over the coming season, I hope to share some of our guidance and tips that help answer the more common questions we’re asked. This month we’ve received a lot of enquiries about gentle pruning, what is it, why use it and critically, does it work:
What is ‘Gentle Pruning’?
Gentle pruning has a few key principles; respect the sap flow, allow controlled branching, never cut old wood, and allow for ‘die-back’.
Why use ‘Gentle Pruning’
It is inevitable that when pruning a vine, wounds are created which could invite pathogens into the permanent structure of the plant. With conventional pruning techniques, these wounds are often found along the trunks, below the spurs and surrounding the crown. Every wound will instigate a certain amount of ‘die-back’ of vascular tissue often called a desiccation cone. The desiccated tissue causes blockages in the vascular bundles and ultimately restricts the sap flow.
Gentle pruning will prevent desiccated cones within the trunk and leading to the crown by keeping all the winter pruning wounds on top of the crown and on 1- and 2-year-old wood only. Wounds on younger wood seal faster and the resulting desiccation cones are shallower. By keeping all the wounds above the crown, you will have no restriction in sap flow leading from the roots to the shoots. Uninterrupted sap flow means that more energy can reach the fruit, shoots and roots. This promotes longevity by preventing a build-up of dead tissue which gets infected easily and can ultimately kill the vine earlier than expected.
How to ‘Gentle Prune’
Applying this method of pruning to guyot style vines will result in a shape of crown that most viticulturists find unfamiliar. The development of branches will create a ‘T’ or ‘Y’ shape that ensures uninterrupted sap flow from roots to shoots. The method is best adopted in the first growing season but conventionally pruned vines can easily be adapted with the first step being at shoot selection time in May.
Start your crowns lower than you would for standard guyot by retaining one green shoot on either side of the trunk (pointing parallel to the rows) at about 25cm-30cm below the fruiting wire. If there are no well positioned shoots, wait until next season and try again. These shoots will be your spur choices that winter and are the start of your branches.
Ensure that each well positioned spur has at least 2 buds on it with the lowest bud coming from the underside and the last bud coming from the top side of
that spur. If the buds naturally fall in the opposite positions, leave a third bud to achieve the correct bud positioning. The bud on top will form your future fruiting cane and the bud below will form your future spur and this is how you keep your wounds at the top- forever.
Following this process year on year with spur on spur each season will build the desired branches which allow for a gradual stepping from mature wood to young wood which is far more natural for the plant than conventional systems allow. After a few years, once the branches have become wider than ~20cm, cross your fruiting canes over the crown to fill the wire and maintain the total buds required, thus not limiting your cropping potential with empty space. A crucial link in the chain of making it effective is to keep your vines balanced at all times. If that shoot you kept on top of the spur at shoot selection last season turns out to be too weak or too vigorous to lay down, you become forced to choose an alternative cane. In his online advanced pruning courses, Glen Creasy explains how to measure and achieve balance within the vineyard. It’s a great course for newcomers and refresher of the facts for experienced vineyard managers.
Does gentle pruning work?
We have seen it working perfectly in vineyards across the UK and abroad where the field teams have taken care to implement the practices over the whole season with clear guidance from the vineyard managers and field supervisors. It takes a few years to build the right structure and it is critical that every operation is carried out correctly and timely but once you’re in the rhythm, you’ll never look back.
If you have a question that you would like support with or would like to see more of our latest vineyard guidance please follow us on social media or contact us Joel@veraison.uk / phone 07761657189 https://veraison.uk/