Many wine lovers have wondered if there is an easy way to tell one grapevine variety from another when visiting a vineyard. It would be fairly easy if we all had photographic memories and could remember the leaf shapes of each variety. Or if we spent our days working in vineyards. But barring those options, leaf coloration in the Fall is probably the easiest way.

A patchwork view of vineyard plots from Davalillo Castle in Rioja. Taken 11/3/2010. Photo: María Alvarez © 2010 Spanish-Wine-Exclusives

The reason it’s much easier to distinguish one variety from another is because Autumn leaf color and the time of the leaf color change vary by grape variety. The change in color is due to the movement of sugar from the leaves to the roots near the end of the vegetative cycle, in preparation for winter. Without sugar nutrients the leaves lose their healthy green color and eventually die off.

Additionally, older and better quality vines for wine production tend to show more vibrant colors than younger and lesser quality vines. The reason for the more vibrant color in old vine leaves is that old vines synthesize more polyphenols than young vines, and these extra polyphenols result more vibrant leaf colors when the sugar migrates away.

The energy in the form of sugar from the leaves is kept in the roots during the winter. When the vegetative cycle starts again in Spring the vine will consume this energy/sugar to grow new leaves and sprout buds. The new green leaves are able to fuel the rest of the vegetative process through photosynthesis.

In the old days in Spain when viticultural knowledge was less scientific and precise, vineyards were planted with “field blends” rather than separated into specific varieties in specific plots. So if you see a multicolored plot, it is most likely a very old vine “field blend” of different grape varieties.

An old vine plot near Laguardia. The mix of different colors makes it easy to see this plot is a “field blend” of different grape varieties. Taken 10/29/2010. Photo: María Alvarez © 2010 Spanish-Wine-Exclusives

Later, as knowledge grew, varieties were separated and planted into the most advantageous plots for each variety. For instance, the white grape Viura tends to do better on slopes, so you will often see plots of Viura planted on sloped sections of vineyards that are mostly planted with the red grape Tempranillo.

The yellow leafed vines are Viura, planted up against the slope. While the redish leafed vines are Tempranillo, and make up the majority of the vines in this vineyard. Taken 10/20/2010. Photo: María Alvarez © 2010 Spanish-Wine-Exclusives

The other key factor to consider when viewing vineyard colors at any particular moment is that each variety of vine has its own vegetative cycle length. For instance Tempranillo has a fairly short, early ripening vegetative cycle, so its leaves change color before those of Garnacha, which has a longer, later ripening cycle. So below you will see that although most of the photos were taken within about a week of each other, the Garnacha leaves are still mostly green and have not fully changed color yet.

Below is a photo catalog of the foliage colors of the primary vine varieties in Rioja.

White grape varieties, in order of decreasing importance in Rioja:

Viura, old vine. Especially bright yellow leaves in the case of this old vine example. Taken 11/3/2010. Photo: María Alvarez © 2010 Spanish-Wine-Exclusives

Garnacha Blanca. Still mostly green; will turn more of a golden yellow at the end of the cycle. Taken 10/29/2010 at the Centro Experimental La Grajera. Photo: María Alvarez © 2010 Spanish-Wine-Exclusives

Malvasia. Still partly green; will turn more yellow at the end of the cycle. Taken 10/29/2010 at the Centro Experimental La Grajera. Photo: María Alvarez © 2010 Spanish-Wine-Exclusives

Red grape varieties, in order of decreasing importance in Rioja:

Tempranillo. A dusty red color. Taken 10/29/2010 at the Centro Experimental La Grajera. Photo: María Alvarez © 2010 Spanish-Wine-Exclusives

Garnacha (Tinto). Still mostly green; will turn more of a golden yellow at the end of the cycle. Taken 10/29/2010 at the Centro Experimental La Grajera. Photo: María Alvarez © 2010 Spanish-Wine-Exclusives

Graciano. Turns a darker, less vibrant red than Tempranillo, but later in the season than Tempranillo. Not fully changed at this point. Taken 10/29/2010 at the Centro Experimental La Grajera. Photo: María Alvarez © 2010 Spanish-Wine-Exclusives

Mazuelo (aka Cariñena). Turns a darker, less vibrant red than Tempranillo, but later in the season than Tempranillo. Not fully changed at this point. Taken 10/29/2010 at the Centro Experimental La Grajera. Photo: María Alvarez © 2010 Spanish-Wine-Exclusives