So it seems like only the first 10% of new vine shots on my grape vines will make flowers/grapes. After that, the vine continues to put out new shoots and keeps extending, but none of the new branches put out any flowers. Is this correct? Or is it related to feeding, or weather, or magic? I pruned my vines while dormant (~January), leaving two main branches. The first few shots did have a chance of having flowers, but they appeared like six weeks ago, and there has been extensive new branches sprouting but no new flowers. Do later branches make flowers?
No, last years growth made the flowers for this year. the new growth is just that. new growth. feed your grapes a fruit production fertilizer. I don't know what brands you may have available to you. do some research and maybe google a "how to" guide or information for the care and maintenance of grapes. table grapes are a bit different than wine grapes but not so different they seem like totally different species. I live in the north and have totally different types to grow than you. check with your local extension service for localized information on growing, pruning, spraying and harvesting. they will probably be more helpful than us. I can give general help but I wouldn't want you to rely on what I know about northern grapes and apply it to southern varieties.
You should check for the variety you have ! I have muscadine type and all my side shoots produce grapes !
