North American Fruit Explorers mailing list at ibiblio

[Lon Rombough <lonrom@hevanet.com>]

Any vine that has a ratio of leaves to fruit that is too low will have poor quality fruit.  It could be because there is too much fruit for the size of the vine, or because the leaves don't get enough light to produce carbohydrates for all those clusters.  Actual size of the vine doesn't matter.  There are vines like the Winkler vine at U.C. Davis and the Hampton Court vine in England that bear over a half ton of fruit each year, and it's full quality fruit (for the variety) because there are enough leaves to take care of the fruit.  I believe the average is about 12 to 15 mature leaves per cluster, but that will vary with variety and conditions.
-Lon Rombough
Grapes, writing, consulting, my book, The Grape Grower, at http://www.bunchgrapes.com  Winner of the Garden Writers Association "Best Talent in Writing" award for 2003.
On Dec 23, 2004, at 2:35 PM, loneroc wrote:

 
Another disadvantage of allowing grapes to climb tree might be that the fruit would be too high to pick.  Lon would know if grape quality might suffer from the tall vines bearing excess fruit.