Sounds like they need more water. I have been told that the leaves let more
water escape from the plant than the roots can take up. Are you pruning the
new leaves off of places on the vine that you dont want them? As long as it
is green you can prune it off anytime. Once it turns brown, wait until the
plant is dormant.

Every week I prune any extra leaves off mine (The ones that start growing up
from the ground or up the trunk). They need more water while they are
putting on fruit than they normally do, also.

Dwayne


"B. Joshua Rosen" wrote in message
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I have a grape arbor with concord grape vines on it. Things were looking
promising for a while but now it seems that the grapes are turning in to
raisins without ever getting to the ripe stage, they are either green (and
bitter) or dried out without anything in between. Does any one have any
experience with concord grapes. BTW I live in Massachusetts.