The decision of when to harvesting grapes is a highly personal one, with weather, variety, desired wine style, and even the winemaker’s personal preferences and experience playing a role. Whether your fruit will be eaten fresh, made into jams or used for wine, knowing how to pick the right time will help you avoid sun damage, vine rot and other unpleasant side effects that can spoil your crop.

Ripeness Tests

When ripeness is near, the grapes will have changed color and a slight sheen, and their texture will change to feel plump and full of juice. Red grapes will slowly turn from green to purple or red, while white varieties will turn from green to yellow.

Seed Color

The color of the seeds is another indicator that your grapes are near ripeness. Before ripeness, the seeds will be white or green (they are extremely tannic and bitter to taste).

The Art of Harvesting Grapes: Tips and Techniques for a Successful Harvest

The best time to harvest your grapes is when they have reached their optimal size and flavor for the varietal. This is called physiological ripeness, and it can vary from vine to vine and varietal to varietal as each is different.

Ripening occurs when the sugar content, or BRIX, in the grapes increases and the acids decrease. This can be measured with a refractometer, which can be purchased on Amazon.

Temperature and Sunlight

As the weather warms up, the leaves on the vine will start to change colors to yellow or orange, which signals that ripening is beginning. However, excessive heat or rain can dilute ripe flavors and harm your grapes.