What is a field blend?

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Dear Dr. Vinny,
What is a field blend?
—Patrick, Chicago
Dear Patrick,
A field blend is a wine made from grapes harvested and fermented together from a vineyard planted to multiple grape varieties (hence the name—the blend is determined by what’s planted in the “field,” rather than by the winemaker). I’ve only seen the term “field blend” applied to wine, but I’m reminded of it when I’m buying flower seeds: There are packets of seeds of one specific species of flower, but there are also mixed packets, like “wildflower blends,” which contain seeds for many different colors and types of flowers. Field blends are like that: Different grapes bring a variety of flavors, structures, colors and acidity levels to the mix.
Field blends can be found all over the world, but they are increasingly rare. These days winemakers prefer to focus on which grapes and even which clones of those grapes might grow best in each specific parcel of a vineyard, and then determining the ideal moment to harvest each of those parcels individually. The winemaker will then vinify each of those parcels separately and determine which lots to blend together and in which quantities, which gives them much more control over the final product.
There are pros and cons to field blends. It’s a rich tradition, and because this style of interplanting grape varieties in a single vineyard has fallen out of favor, those that remain tend to be old vines yielding grapes with concentrated flavors. But it’s very limiting in terms of winemaking choices, and it can be tricky to decide when to harvest, as the various grape varieties don’t all typically ripen at the same time. Co-fermenting the grapes together also poses some challenges, but some vintners believe that the practice can create more harmonious wines.
Field blends are having a moment, though. There’s something romantic about the heritage, authenticity and tradition of a field blend (and some grapegrowers are actually planting new vineyards with the intent of making field blends). In a time when some wine consumers also value non-interventionist or pre-industrial winemaking, field blends hit an attractive note of legacy and tradition.
—Dr. Vinny