I have concord and frontenac grapes for many years. I prune early spring with a center leader and 2-3 lateral branches. Always had fruit except this year. Everything slow and late. First leaves eaten by what but no fruit anywhere. What's wrong and how to correct it? Niles Duluth, Mn
St. Louis County Minnesota
The following website addresses your question:
If flowers were present but no fruit, unfavorable growing conditions or poor pollination are likely factors. If there were no flowers, shade, too much nitrogen should be considered.
Flea beetles sometimes damage emerging grape leaves and grape leaf buds. These pests were abundant in many parts of Minnesota this year.
Sometimes a very heavy crop is followed by little or no fruit the following season.
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