What's the difference between "organic" and "biodynamic" wines?

Dear Dr. Vinny,

There seems to be various levels of "organic," and I'm confused by the way some of the wines are labeled. Could you please clarify the differences between "organic wines," "organically grown grapes" and "biodynamic" wines?

—Allison, St. John's, Newfoundland

Dear Allison,

These differences are difficult to clarify because the rules and regulations that govern them are inconsistent and, in some cases, even in dispute.

Here in the United States, "organic" wines are regulated by law. They are wines made from certified organically grown grapes, and the wines are made without any added sulfites (though naturally occurring sulfites will be present). Wines "made from organic grapes" can include added sulfites, but the grapes must be certified organically grown.

Biodynamic and organic farming both take place without chemicals, but biodynamic farming takes it a step further, incorporating ideas about a vineyard as an ecosystem, and accounting for things such as astrological influences and lunar cycles. The government doesn't certify a wine as Biodynamic®, the independent Demeter Association does. A biodynamic wine means that the grapes are farmed biodynamically, and that the winemaker did not make the wine with any common manipulations such as yeast additions or acidity adjustments. A wine "made from biodynamic grapes" means that a vintner used biodynamically grown grapes, but followed a less strict list of rules in winemaking.

For more information about "green" wines in the United States, see the story we published in the June 30, 2007, issue of Wine Spectator magazine. But be aware that other countries may define all these terms differently.

—Dr. Vinny