grapes changing color

Asked August 24, 2015, 9:50 PM EDT

Hello, I have a grape vine of about ten years old. It has never produced much and some years produces nothing. I live in the Seattle, WA area. This year we have had a very hot summer and I got a LOT of grapes. However, I realized that the grapes are usually on the smaller size and a light purple. This year they are larger and green. And they are ripe, yes. Do grapes change color? I do not remember what kind of grape it is. I have long ago lost that tag. Any ideas? Thanks so much. Adriana

Snohomish County Washington

1 Response

My guess is that the new, green grapes are from the rootstock, not from the plant that was grafted onto the rootstock (that produced your light purple grapes). I think that somehow your grafted plant either did not produce or it died, allowing the rootstock plant to take over.

In western Washington, almost all of the grapes grown here are on grafted vines because of their resistance to disease.