1. Literally (of fruit), to have shriveled and died before being harvested, as due to neglect or lack of resources. With the horrible drought we've had this summer, nearly all of the fruit in my orchards are dead on the vine. You forgot to water my tomato plant! Now they're all dead on the vine!

2. By extension, to have failed prematurely or not come to fruition, as due to being ignored, neglected, impractical, or without the necessary means to succeed. The president made sweeping promises during his campaign, but many of those are now dead on the vine. Many of the resources for students with learning disabilities were dead on the vine following the school board's budget cuts.