WHAT DOES 'OLD VINES' MEAN?
Very old grenache in Roussillon, South of France
very old, brown schist (= a kind of shale)
‘Old vines' indicates that the wine is made from grapes that come from old vines. It is intended as a quality indication. Older vines have an extensive root system that allows them to transport nutrients and minerals from the deepest layers to the plant. Older vines form fewer leaves and grapes.
LESS GRAPES =
smaller harvest, but the relatively small amount of grapes contain concentrated juice with many colouring agents, flavours and fragrances.
SO: OLD VINES = BETTER QUALITY?
This is possible if the old vines are healthy and the winemaker makes good wine from the grapes. The designation alone is in no way a quality guarantee.
How old is old? Nobody can answer that. One producer thinks 15 years is old, the other 50 years. Especially in France and the rest of Europe, vines are only old after 40 years. Outside of Europe, 15 to 20 years is sometimes called old.
Really old vines are older than 100 years. For instance, grenache and zinfandel are grape varieties whose vines can grow exceptionally old and yield very special wines. On www.jancisrobinson.com you will find 'Jancis Robinson's Old Vines Register' with an overview of vineyards with vines that are over 50 years old. There are even 600-year-old vines, found in Nahe (Germany).