One childhood memory many of us share involves sitting in the back seat of the family car at night. Zooming down the road, we gaze out the window at the luminous figure in the night sky and exclaim “the moon is following us!” Our parents might laugh and explain that it’s only an illusion: “Of course, it’s not following us.” But, in a way, it is. While the moon may not be “following” us, it does exert forces that permeate our lives. Scientists debate how much influence over our existence the moon directly wields—if any at all—but no one can dispute that, indirectly, the moon’s presence has affected humanity’s history, art, philosophy, mood, and even how we make wine.

Humans have been enthralled by the moon since the very emergence of our species. Markings in French Stone Age caves suggest that early hunter-gatherers were charting the cycles of the moon as much as 30,000 years ago, perhaps longer. Why wouldn’t ancient peoples note the constant but regular movement of the brightest object in the sky? After all, the most obvious way the moon affects the Earth is with its light. Poets may wax romantic about moonlight, but imagine the absolute darkness of the pre-industrial world’s moonless nights. But when brilliantly illuminated by the full moon (which arrives today as it did in the primordial world—roughly every 29.5 days), nighttime could be as bright as noon. Knowing when nights would be bright or dark would have almost certainly influenced the behavior of early human communities, such as in planning for nocturnal hunts or migrations.

The moon also exerts a gravitational pull on the earth, famously producing our oceans' tides, which rise and ebb every 12.4 hours. The force required to move oceans is immense, fueling ongoing efforts to harness the energy produced by this motion. Science has largely dismissed the belief that, since humans are mostly composed of water, the moon’s gravity would exert a similarly powerful influence over our bodies. Likewise it regards with skepticism the old beliefs that the moon impacts our physiology (as in the menstrual cycle of women) and moods. Yet scientists continue to search for the moon's impact, because the correlation between moon phases and living creatures has indeed been proven. For instance, research has revealed that the mass spawning of corals is synchronized with lunar cycles, triggered by light-sensitive proteins called cryptochromes that can tell the difference between sunlight and moonlight. Cryptochromes in humans might be involved when, as recent studies have found, the moods in bipolar people sometimes do shift according to phases of the lunar cycle. Other studies have tenuously linked phases of the moon with the quality of our sleep.

Whether the moon’s power over our lives is real or imagined, it impacts human life simply because so many people believe it does. That fact is represented incontrovertibly in the world of wine. Farming and viticulture have, since ancient times, been conducted by lunar cycles, a belief adopted by practitioners of biodynamic farming. According to the biodynamic calendar, the moon's position about the Earth determines the best winegrowing practices for each cycle. For instance, full moons exhibit a high gravitational pull, which (supposedly) increases a vine’s sap flow and plant activity, making a full moon night optimal for harvesting grapes. Waning moons are thought to direct a plant’s activity to its roots and are thus considered ideal times for pruning the vine, which encourages root development versus the growing of leaves. The biodynamic calendar divides days into Root, Leaf, Flower, and Fruit. In winemaking, Flower and Fruit days are thought preferable for pressing and racking. These divisions also extend to wine drinking. Flower and Fruit days are considered best for tasting, as wines are thought to be more exuberant. Root and Leaf days aren’t necessarily bad for tasting, but a wine might be more likely to be shut down or lacking in expression on these days.

Does it all sound like a bunch of woo-woo mysticism? Perhaps. But in many years of writing about wine and tasting it, I’ve only met biodynamic growers who rave about the health of their vineyards. Some have even done side-by-side field comparisons between parcels farmed under biodynamic and conventional viticulture, and have unanimously determined the biodynamic vines to be more vital and robust. Many of these growers don’t necessarily believe in the theories behind these practices, but follow the strictures of biodynamic farming nonetheless and are happy with the results.

When it comes to tasting wine, I’ve experienced the biodynamic influence firsthand. Over many trips, tasting at multiple wineries every day for weeks, I’d often forget to check the biodynamic wine calendar app in the morning before setting out. Most days it didn’t matter: I could usually guess whether a day was Fruit or Flower simply because the wines expressed themselves so ebulliently.

So, just because science is skeptical, don’t close the book on the moon’s power. After all, there are many potent and magical-seeming forces that science still can’t explain. For instance, referred to by Einstein as “spooky action at a distance,” the quantum phenomenon of entanglement—when two particles remain connected despite being separated by galactic distances—presently defies explanation. The source of gravity isn't fully understood. And indeed, we don’t even truly know the origin of the moon itself, which makes its influence over us all the more delightful.