Grapevine in my garden last I had grapes, very small but they just rotted on the vine and were very small. What did I do wrong; fed

Question

them every 2 weeks and water every 3 days. Can you help? thank you  I know it was very hot last year; the leaves were green all the time; cut them back so the sun could get through; have had grapevines for about 3 years, this was the first time they had grapes.

Answer 1

This article should help with your problem:

https://www.gardeningknowhow.com/edible/fruits/grapes/black-rot-grape-treatment.htm