The old Roman texts on horticulture warn to keep grapes well watered until the fruit starts to color, but even in fairly hot dry years the grapes here have to fend for themselves.
About a year ago, a local vineyard served me a platter of nice cheese and included a bunch of dried grapes - not only were they still on the stem, but they were seeded grapes. i was very dubious about this offering, but eventually tried a few, and loved them. This year I found that drying seeded grapes turns the hard seed into a crunchy seed, and the grapes/raisins were wonderfully flavored.
So in addition to making lots of raisins for scones (below), i have put whole bunches into my sun-drier to see if i can get a similar result.