A guide to... Harvest

With fingers, buckets & grapes a-quiver; or indeed machines all of a-whir, we take a look at how the harvest actually works. And why it’s such a nail-biting time for producers, viticulturists & consumers alike.


First things first, when?


The exact time of year chosen for harvesting grapes is perhaps the most crucial in the end result. Whilst many of the timely factors could be considered as variable, there is an undeniably fixed influence that sets some steadfast parameters: hemisphere. Wine growing regions in the Northern Hemisphere tend to harvest their grapes in-between August & October; Southern Hemisphere counterparts tend to run in-between February & April. There are, of course, exceptions to rule – things can kick off as early as July in California for that extra bit of acidity & as late as June in cool-climate New Zealand for the sweeter wines.


But what dictates the process kicking into action, & why?


The ripeness of a grape is dependent on its balance between sugar, acid & tannin. This is of course an inconsistent beast: different grapes become ripe in different ways (& at different times) depending on what kind of wine is being created & indeed the personal style and flourish of the winemaker. Throw varying grape blends into the equation & you begin to see just how much rides on the aforementioned flourish & the levels of skill involved.


Previous trends (& indeed this is still current in some Domaines) saw the use of a ‘refractometer’ to guage the acidic levels & properties before they were deemed ready to pick. Now the move is to increasingly more by eye, taste & feel. A more personal & indeed subjective approach vital to ensuring the quality & balance of the end product.


However for grapes to simply ripen at the same time, year on year, is a physical impossibility. Mother Nature, as we all know, does not play her merry dance as such. Climate & weather play huge roles in determining when grapes are harvested & are largely responsible for the variance we see between years, hence the significance of a wine’s vintage.


Ideally grapes benefit from a cool but moist winter, moving into a warm & dry summer. Too much moisture in the summer & grapes can over-ripen, or rot; too little moisture in the winter & sugars can struggle to form. Hail or rain the summer which can destroy ripe grapes, not only paving the way for disease, but decimating that year’s harvest along with. The only time rot is seen as a positive affliction is in the case of noble rot, or Botrytis, creating sweeter wines from certain grapes which have the right properties for the disease to spread. Again this is a timely affair & needs exactly the right moisture/heat balance to spread exactly the right amount. No one said simple.


Which grapes when..?

As we’ve touched upon, there is no such thing as a clockwork regularity when it comes to making wine, but there is a logical order to things. First off we have the grapes destined to make sparkling wine which need to maintain low sugar levels & a high balance of acidity for their two fermentations. Next come the white grapes: this of course depends on the grape, climate, region & wine they are destined to make but earlier harvested grapes will generally be more acidic & with lower sugar levels, the balance shifting the longer they are left to ripen.


Next come the red wine grapes, these take a bit longer to ripen & need that all-important balance of tannin, acid & sugar, the acidic properties of the grape acting as mediator between the two. And last but not least we have the sweet wines as mentioned above: the grapes need longer for the botrytis to set in, concentrate the sugars & yet not too long to lose all of their acidic properties.


The logical question now is how?


Grapes do not simply drop off their vines as & when ready to make their way to be crushed. Although perhaps if they were feeling particularly user-friendly they could then gently roll their way down a hill, forming neat little piles of good & bad grapes at the end of each vine row. Perhaps Mother Nature would entertain a discussion at least..?


For now, grapes are either harvested by hand or by machine, processes which are the source of continual debate within the wine world. Whilst machines make for speedy & cost-efficient (80-200 tons / 24 hours vs our fair hands’ 1-2 tons in the same period) work, they are also far more rough & don’t benefit from the precision of harvest by hand. By hand may be slow & comparatively costly, but the human eye can be selective upon picking & safeguarding quality & saving on further rounds of sifting.


Machine work in two ways: either by slapping the vines with a paddle or shaking them as they drive by. Grapes are then caught by the machine & drawn through a de-debris’ing process into trailers. If the grapes are delicate, or indeed terrain rough or steep, machine harvesting simply isn’t viable, hence many vineyards opting for the more gentle yet laborious hand-harvest. However in really hot & flat climates, machines can be vital as they can be run overnight when the air is cooler & less humid, for transportation back to the winery in the morning.


Then what..?


Once the grapes have made their way back to the winery, by whatever mode & in whatever form has been decided for them, they are sorted by hand or machine, destemmed & prepared for their primary fermentation. This involves removing the skins for white wines, or leaving on for red & then crushed (or just enough skin contact for maceration for rosé), either by foot/hand for the traditionalists, or by a wine-press. They are then ready for their initial fermentation tanks, perhaps with the addition of a little yeast, where they will rest undisturbed the next 1 to 2 weeks. And SO the magic begins…





The Author

Helen Richards

Helen Richards

Hely's love of wine was born from a young age, spending summers exploring the vineyards of France. After studying Modern Languages at Oxford, she worked in publishing and branding before joining the JF Tobias team to help build our blog / written content. She loves wine, writing, yoga and adventure in equal measure and strives to balance all four, although not necessarily all at the same time!