Biodynamics: Some Science, Some Pseudoscience

With Biodynamics becoming an increasingly hot topic in the market and our class discussions, I wanted to debunk the "science" behind the movement.

Biodynamics is a more extreme version of organics, dating back to the 1920s

Defined as a "holistic approach to agriculture," biodynamics is the oldest chemical-free agricultual movement, predating beginnings of organic farming by 20 years (1). Vineyards are viewed as "integrated, whole, living organisms" made up of interdependent eleements - the people, the soil, the fruit, the nearby animals and plants are all interdependent and help the growing process (2). Farmers must use each element to maximize the health of the whole vineyard. No manufactured additions (chemical or otherwise) are allowed at any point in the winemaking process.

A core of the process is creating and using biodynamic preparations to add nutrients to the soil. Mixes of yarrow, chamomile, stinging nettle, oak bark, dandelion, and valerian are added to the soil to "foster the growth of beneficial bacteria and fungi"(3). Additional preparations of horn manure (made from "cow manure buried inside a cow horn" during winter), horn silica (made from "ground quartz crystals buried in a cow horn" during summer), and horsetail tea are added to increase plant immunity and stop fungal diseases.

Source: Wine Folly

One website so scientifically explained: "These preparations act on the compost and especially on the soil where it is spread. They don't add nutrients to the soil, but mobilise elements in the soil and the cosmic environment. They work through the compost like a kind of 'yeast,' increasing vitality and favouring soil health." Ah, yes.

There are some tangible benefits...

According to Demeter (one of the two biodynamic certifiers), soil treated biodynamically has been found superior to both conventionally farmed and organically treated soils in terms of higher carbon content, lower bulk density, and better aggregate stability. It has higher microbial activity, greater biodiversity, and higher nutrient count (4).

A 2005 study analyzing biodynamic vs. organic methods on wine grape quality found that while biodynamic and organic preparations saw limited differences in soil quality, the biodynamically farmed vines had 1) better vine balance (ideal for higher quality wine grapes, vs. overcropped for the organic control vines), 2) significantly higher (p>0.05) Brix, and 3) notably higher (p>0.1) phenols and total anthocyanins. They conclude that biodynamic preparations may have positive influence on wine grape canopy and chemistry.

...But there are also some weird superstitions involved

Biodynamics also have a calendar (1). Each day coincides with one of the four elements (Earth, Fire, Air, and Water --> Fruit, Root, Flower, and Leaf days). These mean:

• Fruit days: Perfect for harvesting!
• Root days: When you prune.
• Flower days: Hands off! Don't touch the vineyard today.
• Leaf days: Water today.

Some even say this calendar corresponds with which days are good vs. not good to drink wine. Note that this Thursday changes from a Flower day to a Leaf day at 4:37PM... (during class time).

Source: Wine Folly

My New Zealand heritage gives me a deep understanding and appreciation for the concepts of treating the land we use with respect, but to me, the whole "leaf day" and "root day" mumbo-jumbo feels like the "mercury is in retrograde" of wine. Sorry to all those loyal to the daily wisdoms of their astrological signs... For now, I need more proof to see biodynamic as superior.