I think it must depend on your climate and your soil. It is really dry here. My neighbor even has Sagebrush in his yard. The few days we have humidity, I think I am going to have heatstroke. These are photos of my trumpet vine that I planted many years ago. It has only sprouted the one baby, and you can see by the size of the original vine that it is really large. It is almost finished blooming, so it isn't really pretty now.
The leaves are a clematis, not the Trumpet in the first photo.
The Woody Vine of my Trumpet Vine
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Trumpet Vine in Bloom
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