We got to see some fabulous oldsters this weekend in Sonoma . That is vineyards with some gnarly old vines (see photo). Fitting since it was Andy’s birthday! To give you some perspective on the impact of vine age on wine, it takes about 3-to-4 years from the time a vine is planted until it bears mature fruit for use in wine. Until then, any grapes produced are discarded.

When a vine is about five years old, it can produce what is considered a full crop. From then to about thirty years, the vine is in full production mode.  After that, the vine slows down and progressively yields less fruit. Vines can live to be over one hundred years old and in fact the ones pictured below, in Sonoma County, are among the oldest in California brought here from Europe by early settlers in the late 1800’s.

 Old Vines and the Soil

It is common wisdom that the soil in vineyards heavily influences the taste and quality of wine.  The essential component of “terroir” (soil, geography and local climate) has a huge impact on grape quality and the distinctiveness of a wine’s character.  Old vines have deeper complex root structures that interact with microorganisms in the soil differently than do younger grapevines.  This supplies the older grapevine with nutrition as well as natural sugars. The rarity and flavor, coupled with smaller yields, explains the label “Old Vines” as well as the higher prices for the more interesting and complex wine product.

There are a small number of vineyards where the grapevines are 60-to-120 years old.  These are called “old vines” and may be labeled as such.  “Old vines” have certain characteristics that make them very special:

Root Depth

As grapevines age, the roots penetrate deeper into the soil and may reach depths of up to 30 feet.  At this root depth, the grapes benefit from soil nutrients, minerals and water not necessarily available at more shallow depths.  These grapevines will not be affected by yearly rainfall inconsistencies or by soil nutrient and mineral deficiencies. Their rootstocks will be very thick.

Berry Size 

As grapevines increase in age, reaching beyond 25 years, the berries become smaller.  This is natural to older vines.  Many wineries will replant at this point to increase yield size and skin-to-juice ratios.  Most of the color and aromas come from the skin of the grape.  Older vines produce a much richer aroma and flavor as well as a deeper wine color.

Lower Yields of Fruit

Energy levels tend to drop off as grapevines age.  They produce fewer vines, smaller clusters and smaller grapes, which also equals more skin-to-juice ratio.    The energy of the plant is concentrated on smaller quantities of grapes.   This translates into wine flavors that are more complex.