Leaf-Thinning in Summer: why we do it (and how)

Summer in Bordeaux may look calm from the outside: vines stretching under the sun, cicadas buzzing, and grapes slowly ripening. But behind that postcard scene, vineyard work continues quietly and carefully.

One of the key tasks at this time of year is leaf-thinning, or as we call it in French: effeuillage.

What is Leaf-Thinning?

Leaf-thinning is the process of removing some of the leaves around the grape bunches. We do it by hand, gently and selectively, often just on the morning-sun side of the row.

At Château Canon Chaigneau, we start around the time of fruit set, and sometimes adjust again before veraison (when grapes start to turn colour).

Why we do it

Like many things in the vineyard, it's all about balance. Too many leaves and the grapes stay hidden, poorly ventilated, and more prone to rot or mildew.
Too few leaves and they burn or ripen unevenly.

Our goal is to:

• Improve air flow around the bunches

• Let just enough sunlight in to warm the grapes

• Avoid disease pressure in case of humidity

• And ultimately: encourage healthy, even ripening

It’s especially important in our clay-limestone soils, where vegetation can be generous. We don’t want to clip too much: just enough to open the canopy and let the grapes “breathe.”

How we do it at Canon Chaigneau

We remove leaves by hand, working row by row in the early morning.
We:

• Target only the east-facing side (morning sun)

• Focus on the fruiting zone, not the top of the vine

• Leave enough leaf cover for shade and photosynthesis

The process is slow, thoughtful, and physical. But it’s one of the reasons our Merlot and Cabernet Franc reach maturity with balance and energy.

More than just a technical step

Leaf-thinning is also a way to walk the vineyard, observe the vines, and stay connected with what’s happening.

Some years, we do less. Some years, more. It all depends on:

• The weather

• The vintage profile

• The vine's natural balance

As always, listening to the plant is the first step in making great wine.

If you’d like to see effeuillage in action, check out our latest post on Instagram, or better yet, come walk the rows with us next summer.