We have a couple grape vines, which we've had for years. Normally, they'll set fruit once, early in the season, and it would be ripe later in the season. This year, one of them—and to a lesser extent, another one of them—has been setting fruit far beyond the normal period. I looked at it today, and it's still setting new fruit (we're near the end of the average growing season for my area). Is this normal? Why doesn't it do this every year?
The main one I'm talking about is said to be a black variety, or maybe it's dark purple (it doesn't have that extra fruity flavor like Concord). I don't know what it is. The other one is Thompson Seedless.
I'm in southwestern Idaho, my part of which has a BSk climate (with very hot summers and late springs). We had a hot and an extra-dry summer, this year, with a much cooler-than-average late spring.
The grapes are infested with leaf hoppers, as they have been every year for a few years. However, they seemed to be free of them for much of the season.
The main difference this year is that they have more sun, since there aren't any trees in the garden, now. We've had probably as much sun before, without this result—but it's been a long time.