Trumpet vine

https://www.gardeningknowhow.com/ornamental/vines/trumpet-vine/trumpet-vine-no-blooms.htm

I would think that perhaps it needs some amendment to the soil. Generally, these guys do well with "benign neglect". Also, don't bother with watering them - again, benign neglect lol!

This plant takes several years to reach maturity and be ready to bloom. If the trumpet vine was grown from seed, it can take 10 years for it to be old enough to bloom. Too much fertilizer or soil that is too rich can cause trumpet vines that do not bloom.

Look at my favorite site for other information on trumpet vines:

Trumpet Vine No Blooms: How To Force A Trumpet Vine To Flower

https://www.gardeningknowhow.com/.../vines/trumpet-vine/trumpet-vine-no-blooms.ht...

Needs a male and female plant to bloom

I honestly can't say for sure. My father had a beauty that grew in shade under pine trees. My uncle had his across the street in bright sunshine that was a beauty too where a pine tree use to stand before it was hit with lightening. So....could it need acid? Also, the dirt is kind of sandy too where both are planted. I'd try acid for plants.

I didn't know there was a need for male and female for trumpet vine.