We have three grape vines that have been in our yard for about 20+ years. I took over the "garden" a couple of years ago. Every year late in the fall we cut back the grapes. We get a lot of new growth each year but no grapes! Are the plants just too old to produce? Or do they need something?
Older Grape Vines
Certified GKH Gardening Expert
Even plants can eventually "poop out". Stress on the plant will also affect the productivity of the fruit. Make sure that the soil is balanced. I would recommend having it tested, if you have not done this before. Then add amendments based on what the soil is lacking. And lastly, make sure that there are no pests or fungus affecting the vines. If there are, treat the plants accordingly.