When to trim grape vine in San Francisco Bay Area?

Question

We just moved to Menlo Park and there is a grape vine trained along the fence which appears to need to be trimmed. When is the best time to trim it, and how?

Answer 1

The best time to prune back grapes in the South Bay is late winter or early spring, before the new leaf buds break and while the vine is still dormant. There are a few various techniques applied to pruning grapes and an explanation here at Y/A would be quite long winded for sure. With that said, I will hook you up to a link from Oregon State University (my old alma mater)...Go Beavs Go!....Oh Sorry, I must of had an orange & black flashback attack..lol. This link has a very in depth explanation along with a nice pictorial of pruning techniques to go along with the whole shebang. Hope this helps you out. Have a Happy New Year!
http://extension.oregonstate.edu/catalog/html/ec/ec1305/#prun

...$Billy Ray$

Answer 2

Living in Missouri Wine country gives me great opportunity to tour the vinyards. I live about 10 minutes from the nearest vineyard.
Grapes should be pruned during the dormant season, late November to March, that's in MO.
Having lived in the Bay area/San Francisco/Oakland/Alameda for many years your dormant period is way later than here in this state.
In your area planting should be done in December and pruning as well, all the way to February with a light summer pruning for a possible hastening of fruit development.
http://www.groworganic.com/greybox.html?pBoxName=GrowGrap
Home Page
http://www.groworganic.com/item_FV055_California_Concord_Grape_Vine_ea.html?welcome=T#
Good Luck!
PS if your from CA ..Encinal HS in Alameda &Stanford U. #1 Gennessee Street San Francisco