7 Burgundy vineyards are pushing forward research into combatting spring frosts

he ‘PhysioVigne’ project launched in 2022 has produced the first results on late pruning and post-frost desuckering. The consortium of wineries and researchers focused its first experiments on late pruning by comparing conventional pruning in February with later pruning at the end of March and very late pruning at the end of April in Chardonnay and Pinot vineyards in 2021, 2022 and 2023. Delaying pruning put bud-burst back by up to 8 days, but also led a significant decrease in the number of clusters and yield for two in three vintages. “These results confirm the risks of depleting the vine’s resources when pruning is conducted too late after crown buds have burst, at a time when its carbon reserves are already being strongly drawn upon”.

The consortium also worked on post-frost desuckering by conducting comparative trials on several frost-affected blocks belonging to the project’s sponsors. The results did not show any significant difference between desuckering and absence of desuckering on yields. However, desuckering did lead to a slight “catch-up” on the physiological gap caused by the frost spell. The trials also allowed the consortium to confirm the differences in bud fertility, depending on the type of canes, with “improved fertility for buds on rows higher than 2 on the rod compared with renewal spurs, where fertility in turn was higher than for buds on old canes”, and depending on the nature of the buds on fruit-bearing canes, with “higher fertility for latent buds than for ‘double-bud down’ which in turn was higher than for ‘crown buds’”.