De-leafing

To de-leaf or not to de-leaf? A divisive question in the viticultural world.
De-leafing means removing the two lowest leaves from each vertical shoot, and thus exposing the developing grape bunches to direct, rather than filtered, sunlight.

Proponents cite the following advantages…

1) Improved ripening and flavour development, probably due to the increased temperature as the berries absorb direct sunlight.
2) Reduced risk of bunch rot due to reduced humidity in the fruit-zone. This is a big plus if you want to avoid using anti-rot sprays (which are anyway prohibited by organic certification)
3) Reduced risk of Powdery mildew (Oidium).
4) Faster harvest since the bunches are clearly visible

While opponents cite the following disadvantages

1) Increased risk of ‘sunburn’ – where on a hot, bright day fully exposed grapes simply shrivel and die.
2) Fewer remaining leaves to photosynthesise sugars.
3) Increased losses in the event of hail – since the leaves provide a small degree of physical protection.
4) The time and hence cost involved; I take about 80 hours to de-leaf two hectares, which if I were to pay someone minimum wage (it’s not rocket science!) would add about 0.13€ per bottle.

As the photo shows I am in a very small minority (in Burgundy) who decide that the pros outweigh the cons. To minimize the sunburn risk I only de-leaf the north (or east) side of each row and I start immediately after flowering so the grapes can acclimatize to exposure before they are fully-grown and at their most vulnerable.

One more good day’s work and I’ll be done with this job, and I won’t be sorry to see it finished! I figure I’ve de-leafed 20 kilometres of vine rows, or removed approximately 280000 leaves.