Domenico Winery + Osteria

A sunny date in the vineyard during harvest

7 Wine Harvest Facts You Should Know

September is here and you know what that means – grape harvest! Of course, harvest can begin before this, especially with the 2022 summer heat. Either way, September is a busy month for wineries all over the Northern Hemisphere. Grapes are coming in fast and need TLC. As a wine lover, you should know these 7 wine harvest facts. Keep them in your pocket – they’ll be helpful as you navigate wine, every sip of the way.

7 Wine Harvest Facts You Should Know

Harvest doesn’t have an exact start date every year

Winemaking relies a lot on nature. And, as we know, Mother Nature can be unpredictable at times. So, harvest isn’t a set period during the year.

Of course, harvest happens around a specific period. Wine harvests in the Northern Hemisphere typically happen anywhere between August and November. If we’re talking about the Southern Hemisphere, it’s anywhere from February to even early May.

When harvest starts and ends all depends on various factors, apart from the weather. Winemakers consider the type of grapes, where they’re grown, and the style of wine they’re making. The ‘when to pick grapes’ topic can go on for books. So, we’ll keep it simple and stop here.

The Brix matters

There’s an essential measurement during harvest, and it’s called Brix. This unit tells a winemaker how much sugar is in a grape or fermenting wine, which provides a rough estimate of the expected alcohol content.

Measuring Brix will give winemakers a solid idea of when to pick grapes. They head to the vineyards to get grape bunch samples, crushing them for their juice and testing it with a refractometer. This tool measures the Brix of the grape juice.

When it comes to white wines, winemakers often aim for a lower Brix than in red wine. The lower Brix means more acidity and less sugar, something you typically want in white wine. Of course, we know that this statement isn’t always true. But, it can help explain why wineries pick white wine grapes earlier than red wine grapes.

Sparkling wine grapes are first

Now that you know Brix, the following wine harvest fact shouldn’t be surprising. Since sparkling wines require a base wine with high acid and low alcohol content, the grapes themselves shouldn’t be incredibly ripe. That’s why grapes for sparkling wine are almost always harvested first.

Freshly harvested grapes

Freshly picked grapes can’t hang around

Grapes are fresh fruit, whether they’re table grapes or wine grapes. The fruit has sugar only waiting to begin fermenting. And, no winemaker wants their grapes to start having a fermentation party before entering the winery.

That said, it’s crucial to bring freshly picked grapes to a cool place and process them as soon as possible. When grape bunches pile up in bins during harvest, their weight can slightly crush some grape bunches. Combined with the heat, grapes could also begin fermenting. Plus, sitting in the hot sun will deteriorate the grapes’ quality, losing influential flavors and aromas.

Winemakers don’t crush grapes with their feet…

There exists a romanticized idea of winemaking, one where winemakers pile fresh grapes into wooden vats and stomp them vigorously to make wine. If wine was made only this way, there would be a lot less of it.

The reality is that professional equipment exists to process grapes less laboriously and more consistently. And, this equipment is used by wineries big and small to process the grapes. There is the crusher/de-stemmer and the grape press. These two pieces of equipment come in various sizes and levels of complexity. For example, a press can vary from an old-school basket press to a 20-ton bladder press.

White grapes are crushed and pressed first (usually)

To keep white wines pure in color, white wine grapes are typically processed first. Or else, you’ll have white wine with a pinkish hue. The protocol in a winery goes: white grapes go first or else you have to clean all your equipment after crushing your red grapes (which is a real pain and why white grapes go first if they can.)

This practice is generally easy since white wine grapes typically arrive at the winery first. However, there can be a lot of overlap since wineries tend to work with various wine grapes and winemaking styles.

Freshly picked white wine grapes

Grapes can be processed in a lot of ways

Yes, wine comes from fermented grape juice. But, there’s a lot more that goes into it. How a winemaker treats grapes in the winery defines the entire wine’s life. This process begins in the vineyard (remember Brix?) Yet, to keep things focused, we want to remind you – not all grapes are handled the same.

The simplest example is white wines and red wines. Generally speaking, white grapes are destemmed, crushed, and pressed immediately. The juice goes to ferment and there’s your white wine. Yet, red wine grapes are destemmed and crushed, then the grape skins and the juice rest together. The skins are where red wines get their color.

Now, this is a basic example of processing. However, it gives you the foundation, the baseline of winemaking. Winemakers can experiment with how they crush the grape bunches if they even want to stem all of them, and how much skin contact they want. These things go for white and red grapes alike. These choices all rely on the winemaker’s vision for the future wine.

We could go on from here with wine harvest facts, into the realm of winemaking. But, that’s saved for another time! Until then, don’t be shy to explore our other resources on California wine, Italian grape varietals, delicious Domenico wines, and more on our blog.