The vines are 8 years old. Have produced grapes every year but this year grapes are growing in great clusters but are falling off when green. We prune as we should. We had a lot of rain this year. There is no fungus or anything on the vines or grapes or leaves. I read all 21 pages of your posts and there is nothing like this. I didn\'t include a photo because the grapes are green and perfect.
Certified GKH Gardening Expert
There are several possible causes of premature fruit drop including:
- too much or too little water
- nutritional deficiency or excess (such as too much nitrogen)
- fungal problems such as powdery mildew (look for a white haze on fruit)
- insect feeding
- poor pollination
- a lack of light (grapes need full sun)
So, there may me one or more causes. A soil test would be smart to look at the nutritional issue. Inspect the vines for insects or fungal growth. Encourage pollinators with diverse plantings.