Hi all! There is a flowering vine I see growing all over my neighborhood and on public property on the way home. The leaves are green and grow profusely, especially all over fences. They have a flower that seems to only come out in late summer and early autumn. The flower is shaped a bit like a petunia and is a beautiful deep deep purple. Does anyone know what this is called or where I can buy it? If someone gave me a cutting, would it have to be taken out by the roots in the ground or could I put it in a glass of water and root it?

Thanks!