Answer: Trumpet vines bloom on the new growth of the season, so dying back to the ground would not specifically affect that. However, the plant may be suffering cumulatively from stress that is causing the dieback. Trumpet vine is only hardy to zone 5, so it is possible that the location is too cold for it. Another possibility is that the location is too shady, since this plant grows best in a full sun location. It could also be in a location that is overly moist in winter, causing the roots stress and weakening the plant. Finally, some individual plants seem to be shy and take their time about blooming. Perhaps your vine is one of these in which case it should begin to bloom more heavily from year to year. I hope this helps you trouble shoot.
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