Know your Vines #8: See patterns in how your grapes are ripening & predict your harvest date earlier

Know your Vines #8: See patterns in how your grapes are ripening & predict your harvest date earlier 2000 1333 Sectormentor for Vines

In our Know your Vines blog series we share practical tips on what metrics to monitor in your vineyard. This is the eighth instalment, stay tuned for more as the seasons unfold! “If you can’t measure it, you can’t improve it.


Monitor grape sugar and acidity to get the balance just right – all made easier with our Grape Ripeness Indicator Tool

As we get closer to harvest, life is getting sweeter for grapes! They are beginning to ripen, which means sugars are generally increasing whilst acidity is dropping. Many vineyards monitor sugar and acidity levels as harvest approaches to help them decide when to start picking. Of course, this is not purely a science, as we are looking to make delicious wine, so tasting the grapes is a key part of the equation. It’s the combination of the art of taste, and the science of sugar and acidity levels that helps ensure you have a smooth well-timed harvest for each block in the vineyard.

Vines at Rathfinny Vineyard

Monitoring sugar and acidity levels
Post veraison, vineyard managers/winemakers regularly monitor the sugar and acidity levels of grapes across the vineyard. A refractometer is used to measure grape sugar, giving a Brix or Oechsle reading. Titratable acid, the total acid content in grape juice, is important for balancing a wine and is measured by neutralising the grape juice with an alkaline solution. It’s important to take a representative sample of grapes when measuring these and to use the same juice for both tests to get a real understanding of the sugar to acid ratio.

These are two of the ten key metrics to monitor in the vineyard. Sectormentor for Vines makes it quick and easy to record all this information and share it with the vineyard and winemaking team so they can see what is happening with the grapes.

Chalk House Vineyard

Veraison at Chalk House Vineyard

Using the Sectormentor Grape Ripeness Indicator Tool
When you record sugar and acidity readings using Sectormentor for Vines, we automatically plot them on a graph. This makes it easy to see how the ripening is progressing, as it’s not always linear. Weather events have a big impact on ripening and it is helpful to see this displayed graphically.

Davenport Vineyards sugar and acidity levels for different varieties in 2018

Every block with a different variety, clone and rootstock behaves differently, so with this data you may start to see patterns and relationships between blocks. In the graph above you can see how the sugar and acidity levels vary for each variety, and the difference in how quickly each one ripens. Will, at Davenport Vineyards, can use this information to plan when to harvest each variety and the graph is easy to share with his team.

Davenport Vineyards comparison of sugar and acidity levels year on year for a single variety

By comparing ripeness data year on year for the same block it’s possible to identify patterns particular to each block. How long does ripening tend to take for this block? Is this year similar to 2016? Comparing to other similar years will also help you predict harvest dates based on the ripening trajectory.

Are you already using Sectormentor for Vines to monitor sugar and acidity? Log into your Sectormentor account online to try our updated Grape Ripeness Indicator. You’ll find it in the ‘Tools’ section – let us know what you think!


Find out how Sectormentor for Vines helps you record data & manage your vines for the best quality grapes: get in touch here or check out 10 key metrics to monitor in your vineyard.