4 year old Trumpet Vine - Never Flowered

[Stubbornhillfarm]

That about sums it up! Any ideas why?

It's in full sun, leaves and runners grow well, but never any flowers.

 

[catjac1975]

They need to be mature to flower. Give it limestone and fertilizer and more time. Prune it to one main stem. In time it will become woody and an invasive pain. I am still glad I have it-it is now in bloom and lovely. Here they bloom in July-probably later where you are. I saw one once that was braided to form a large woody stem and it bloomed from the top-stunning. I bought a yellow that has never bloomed-just became invasive. I don't even know if it is yellow. They like a lot of sun and the yellow is in partial shade. I cannot even kill it.

 

[seedcorn]

Blooms are on new growth. Prune in spring, will not bloom. Have to prune in fall.

 

[thistlebloom]

Like Cat said, your trumpet vine is still young, they sometimes don't bloom until they are 10 years old. :/
Besides waiting until you're old to see blooms you can sometimes stress a plant into blooming by doing some root pruning.
In late fall use a shovel to cut vertically around the plant, about 2 feet away from the trunk.
You can also fertilize it with bonemeal or a fertilizer with 20 as the middle number. Don't use one with nitrogen, or you'll just be getting lots of lush leaves.

Is it getting sun all day?

Oh, right, you said it was.

 

[lesa]

Patience! Mine took forever too...Now it is covered in blooms. Someone near me has theirs trimmed like a tree from, with the top in blossom. Very pretty!

 

[Stubbornhillfarm]

Yikes! OK Thanks. Maybe I will see if I can do some creative braiding or something. It is becoming invasive at this point. If it was flowering I wouldn't mind. I'll try the fertilizer too! And maybe some messing with the roots in the fall. Thanks again.